Free tool

LEGO Missing Piece Checker

Rule out the usual hiding places first. If the piece really is gone, check the set piece by piece and leave with the element ID LEGO asks for, or a link to buy the part.

Dinosaur Fossils

Checking

21320 Dinosaur Fossils

900 pieces in 196 part and color combinations, plus 2 minifigures.

LEGO counts 910 pieces. This inventory comes from a separate parts catalog and lists 911, including the 11 parts inside the minifigures; the two do not always count the same elements, so their totals differ. Spare parts are counted in neither figure.

Before you call it missing

Builders who report a missing piece often find it in one of these places. Tick each one off as you look.

Look-alike colors in this set

These parts appear in this set in two colors that are easy to confuse. If you are one short in one color, check whether it went in where the other color belongs. Each color has its own element ID in the parts list at the back of the instructions.

Show

Piece checklist

White 605 pieces

  • Animal Body Part / Plant, Tail / Claw / Horn / Branch / Tentacle, End Section White Part 40379 Element 6110023 or 4508454 ×22
  • Animal Body Part, Barb / Claw / Tooth / Talon / Horn, Medium White Part 87747 Element 6270092 or 4613941 1 spare in the box ×2
  • Animal Body Part, Barb / Claw / Tooth / Talon / Horn, Small White Part 53451 Element 6270106 or 4568387 2 spares in the box ×15
  • Animal Body Part, Dog Bone [Short] White Part 93160 Element 6360202 or 4600294 1 spare in the box ×2
  • Arm Mechanical with 2 Clips [Battle Droid] White Part 30377 Element 6321345 or 4260649 1 spare in the box ×2
  • Arm Mechanical with Clip [Thick Support] White Part 98313 Element 6976864 or 6276864 ×2
  • Bar Holder with Clip White Part 11090 Element 6341465 or 6136789 ×31
  • Bracket 1 x 1 - 1 x 1 Inverted White Part 36840 Element 6548290 or 6242241 ×10
  • Bracket 1 x 2 - 1 x 2 White Part 99781 Element 6552141 or 6548275 ×1
  • Bracket 1 x 2 - 1 x 4 [Rounded Corners at Bottom, Square Corners at Top] White Part 28802 Element 6548284 or 6168618 ×2
  • Brick Arch 1 x 2 Jumper White Part 38583 Element 6615524 or 6278396 ×2
  • Brick Arch 1 x 3 x 2 White Part 88292 Element 4568956 ×4
  • Brick Curved 1 x 2 x 1 1/3 with Curved Top White Part 6091 Element 6285777 or 609101 ×3
  • Brick Curved 2 x 1 No Studs [1/2 Bow] White Part 11477 Element 6552145 or 6548276 ×18
  • Brick Curved 2 x 2 x 2/3 White Part 15068 Element 6552147 or 6047220 ×5
  • Brick Curved 3 x 1 No Studs White Part 50950 Element 6548268 or 4249112 ×2
  • Brick Curved 4 x 1 No Studs [Stud Holder with Symmetric Ridges] White Part 11153 Element 6578744 or 6564905 ×6
  • Brick Curved Inverted 2 x 1 White Part 24201 Element 6601928 or 6172927 ×21
  • Brick Curved Inverted 4 x 1 White Part 13547 Element 6552146 or 6034675 ×2
  • Brick Round 1 x 1 Open Stud White Part 3062b Element 6619283 or 306201 ×2
  • Brick Sloped 30° 1 x 1 x 2/3 (Cheese Slope) White Part 54200 Element 6550179 or 4504369 2 spares in the box ×29
  • Brick Sloped 45° 2 x 1 Triple with Inside Stud Holder White Part 15571 Element 6619295 or 6097801 ×2
  • Brick Sloped 45° 2 x 1 with 2/3 Cutout [New Version] White Part 15672 Element 6552150 or 6550153 ×4
  • Brick Sloped Inverted 33° 3 x 1 with Internal Stopper and No Front Stud Connection White Part 4287c Element 6552111 or 428701 ×2
  • Brick Sloped Inverted 45° 6 x 1 Double with 1 x 4 Recessed White Part 52501 Element 4259937 ×2
  • Brick Special 1 x 1 Studs on 4 Sides White Part 4733 Element 4111971 or 473301 ×6
  • Brick Special 1 x 1 with Headlight White Part 4070 Element 6548267 or 407001 ×2
  • Brick Wedged, Curved 2 x 1 with Stud Notch Left White Part 29120 Element 6552168 or 6213880 ×5
  • Brick Wedged, Curved 2 x 1 with Stud Notch Right White Part 29119 Element 6552169 or 6213881 ×5
  • Brick Wedged, Curved 2 x 3 x 2/3 Two Studs, Wing End White Part 47456 Element 4610897 ×1
  • Brick Wedged, Curved 3 x 4 x 2/3 Cutout White Part 11291 Element 6179658 or 6019163 ×2
  • Food Egg with 1.5mm Hole [Plain] White Part 24946 Element 6550158 or 6143595 ×1
  • Hinge Brick 1 x 2 Base White Part 3937 Element 6619287 or 393701 ×2
  • Hinge Brick 2 x 2 Top Plate Thin White Part 6134 Element 6548272 or 4612342 ×2
  • Hinge Cylinder 1 x 2 Locking with 2 Click Fingers and Axle Hole, 9 Teeth White Part 30553 Element 6194850 ×4
  • Hinge Plate 1 x 2 Locking with 1 Finger On End, without Groove White Part 44301b Element 6266219 ×9
  • Hinge Plate 1 x 2 Locking with 1 Finger On Top White Part 30383 Element 6265695 or 4262011 ×1
  • Hinge Plate 1 x 2 Locking with 2 Fingers On End, without Groove, 9 Teeth White Part 44302b ×12
  • Hinge Plate 1 x 2 Locking with 2 Fingers on Side, 9 Teeth White Part 60471 Element 6615546 or 4515337 ×1
  • Hinge Plate 1 x 4 Swivel Top / Base - Solid Clip [Complete Assembly] White Part 73983 Element 6102776 or 4287153 ×4
  • Hinge Plate 2 x 2 Locking with 1 Finger on Top White Part 92582 Element 6265740 or 4613762 ×1
  • Mudguard 2 x 4 with 2 x 2 Studs and Flared Wings White Part 41854 Element 4549393 or 4163943 ×1
  • Panel 1 x 2 x 2 [Side Supports / Hollow Studs] White Part 87552 Element 6615549 or 4585458 ×1
  • Plate 1 x 1 White Part 3024 Element 6548262 or 302401 1 spare in the box ×5
  • Plate 1 x 2 White Part 3023 Element 6552100 or 6548261 ×2
  • Plate 1 x 3 White Part 3623 Element 6552105 or 6550144 ×4
  • Plate 1 x 4 White Part 3710 Element 6552108 or 6548266 ×4
  • Plate 1 x 6 White Part 3666 Element 6552107 or 6548265 ×3
  • Plate 2 x 3 White Part 3021 Element 6550136 or 302101 ×1
  • Plate 2 x 4 White Part 3020 Element 6552098 or 302001 ×7
  • Plate 2 x 6 White Part 3795 Element 6550146 or 379501 ×4
  • Plate 3 x 3 White Part 11212 Element 6552153 or 6104805 ×1
  • Plate 4 x 6 White Part 3032 Element 303201 ×1
  • Plate Round 1 x 1 with Open Stud White Part 85861 Element 6168642 or 4547649 1 spare in the box ×8
  • Plate Round 1 x 1 with Solid Stud White Part 6141 Element 6601919 or 614101 1 spare in the box ×2
  • Plate Round Corners 2 x 6 Double White Part 18980 Element 6147792 ×6
  • Plate Special 1 x 1 Rounded with Handle White Part 26047 Element 6564914 or 6174937 ×10
  • Plate Special 1 x 1 with Clip Light, Bar Hole [Thick Ring] White Part 4081b Element 6281990 or 4632566 ×3
  • Plate Special 1 x 1 with Clip Vertical [Thick Open O Clip] White Part 60897 Element 6330191 or 4613256 ×4
  • Plate Special 1 x 1 with Tooth White Part 49668 Element 6601935 or 4224792 ×20
  • Plate Special 1 x 1 with Vertical Tooth White Part 15070 Element 6615559 or 6046905 ×3
  • Plate Special 1 x 2 Rounded with 2 Open Studs White Part 35480 Element 6552167 or 6550175 ×38
  • Plate Special 1 x 2 [Side Handle Closed Ends] White Part 48336 Element 6552125 or 4222017 ×4
  • Plate Special 1 x 2 with 1 Stud with Groove and Inside Stud Holder (Jumper) White Part 15573 Element 6550152 or 6051511 ×19
  • Plate Special 1 x 2 with Angled Handles on Side White Part 92692 Element 4622937 ×3
  • Plate Special 1 x 2 with Clip Horizontal on End White Part 63868 Element 6361170 or 4535737 ×6
  • Plate Special 1 x 2 with Handle on End [Closed Ends] White Part 60478 Element 6552131 or 4515364 ×3
  • Plate Special 1 x 2 with Handles [Flat Ends / Low Attachment] White Part 3839b Element 6619286 or 383901 ×2
  • Plate Special 1 x 2 with Pin Hole on Top White Part 11458 Element 6632146 or 6057414 ×4
  • Plate Special 1 x 2 with Three Teeth [Tri-Tooth] White Part 15208 Element 6046381 ×7
  • Plate Special 1 x 3 with 2 Studs with Groove and Inside Stud Holder (Jumper) White Part 34103 Element 6550171 or 6195371 ×4
  • Plate Special 1 x 4 with 2 Studs with Groove [New Underside] White Part 41740 Element 6249091 ×4
  • Plate Special 2 x 2 with 1 Pin Hole [Complete Underside Rib] White Part 10247 Element 6552149 or 6061024 ×8
  • Plate Special 2 x 2 with Groove and Center Stud (Jumper) White Part 87580 Element 6550157 or 6126046 ×5
  • Plate Special 2 x 2 with Only 2 studs White Part 33909 Element 6552170 or 6548287 ×1
  • Plate Special 2 x 2 x 2/3 with Two Studs On Side and Two Raised [Solid Anti-stud] White Part 99206 Element 6046979 ×1
  • Plate Special 2 x 3 with Rocks White Part 27261 Element 6181319 ×2
  • Plate Special 3 x 2 with Rounded End, Hole White Part 3176 Element 6609537 or 6089696 ×2
  • Plate Special Round 2 x 2 with Center Stud (Jumper Plate) White Part 18674 Element 6615555 or 6093053 ×2
  • Technic Axle and Pin Connector Angled #4 - 135° White Part 32192 Element 6262904 or 6137758 ×4
  • Technic Beam 1 x 11.5 Double Bent Thick White Part 32009 Element 6271161 or 6004157 ×2
  • Technic Beam 1 x 7 Bent (4 - 4) Thick White Part 32348 Element 6278132 or 4509912 ×6
  • Technic Beam 1 x 9 Bent (6 - 4) Thick White Part 6629 Element 6279886 or 6063839 ×6
  • Technic Brick 1 x 1 with Pin Hole White Part 6541 Element 6609542 or 654101 ×4
  • Technic Plate 1 x 5 with Smooth Ends, 4 Studs and Centre Axle Hole White Part 32124 Element 6280386 or 4527839 ×7
  • Tile 1 x 2 with Groove White Part 3069b Element 6548264 or 306901 ×4
  • Tile 1 x 3 White Part 63864 Element 6552134 or 6548270 ×6
  • Tile 1 x 4 with Groove White Part 2431 Element 6548255 or 243101 ×4
  • Tile 1 x 6 with Groove White Part 6636 Element 6548296 or 663601 ×2
  • Tile Round 1 x 1 Half Circle White Part 24246 Element 6609539 or 6250591 2 spares in the box ×54
  • Tile Round 1 x 1 Quarter White Part 25269 Element 6548285 or 6172366 1 spare in the box ×2
  • Tile Special 1 x 1 with Clip with Rounded Edges White Part 15712 Element 6348055 or 6054551 ×9
  • Tile Special 1 x 2 with Two Vertical Teeth / Tooth White Part 15209 Element 6046384 ×23
  • Tile Special 2 x 2 Inverted White Part 11203 Element 6564913 or 6013866 ×1
  • Tile Special 2 x 3 Pentagonal White Part 22385 Element 6550174 or 6245249 ×2
  • Tile Special Round 1 x 1 with Hollow Bar White Part 20482 Element 6186681 or 6178492 1 spare in the box ×4
  • Wedge Plate 3 x 2 Left White Part 43723 Element 6552121 or 4179875 ×1
  • Wedge Plate 3 x 2 Right White Part 43722 Element 6552120 or 4179874 ×1
  • Wedge Plate 3 x 4 with Stud Notches [Reinforced Underside] White Part 90194 Element 6170524 or 4649049 ×1
  • Wedge Plate 4 x 4 with 2 x 2 Cutout White Part 43719 Element 6275403 or 4561038 ×1
  • Wheel Arch, Mudguard 2 x 4 Studded with Hole White Part 60212 Element 4600181 or 4520807 ×1
  • Wheel Arch, Mudguard, 1 1/2 x 6 x 1 [Arch Extended] White Part 62361 Element 6476001 or 4523556 ×4

Black 89 pieces

  • Brick 1 x 1 Black Part 3005 Element 300526 ×2
  • Brick 1 x 10 Black Part 6111 Element 611126 ×4
  • Brick 1 x 2 Black Part 3004 Element 300426 ×2
  • Brick 1 x 6 Black Part 3009 Element 300926 ×4
  • Brick 2 x 4 Black Part 3001 Element 300126 ×1
  • Equipment Magnifying Glass with Thick Frame, Solid Handle, Trans-Clear Lens Pattern Black Part 10830pat0001 Element 6012466 ×1
  • Hinge Cylinder 1 x 2 Locking with 2 Click Fingers and Axle Hole, 9 Teeth Black Part 30553 Element 4143372 ×2
  • Hinge Cylinder 1 x 3 Locking with 1 Finger and Technic Friction Pin with Round Hole Black Part 41532 Element 4159335 ×1
  • Hinge Plate 2 x 2 Locking with 1 Finger on Top Black Part 92582 Element 6265730 or 4613759 ×1
  • Lipstick [Plain] Black Part 93094 Element 6528721 or 6221606 1 spare in the box ×1
  • Panel 1 x 4 x 1 with Rounded Corners [Thin Wall] Black Part 15207 Element 6092570 ×5
  • Plate 1 x 2 Black Part 3023 Element 302326 Also in Dark Bluish Gray ×1
  • Plate 2 x 2 Corner Black Part 2420 Element 242026 ×2
  • Plate 6 x 10 Black Part 3033 Element 303326 ×6
  • Plate 6 x 6 Black Part 3958 Element 395826 ×1
  • Plate Special 1 x 2 with 1 Stud with Groove and Inside Stud Holder (Jumper) Black Part 15573 Element 6092585 ×2
  • Plate Special 2 x 2 with Only 2 studs Black Part 33909 Element 6192346 ×2
  • Plate Special 2 x 2 x 2/3 with Two Studs On Side and Two Raised [Solid Anti-stud] Black Part 99206 Element 6052126 ×1
  • Plate Special 3 x 4 with 1 x 4 Center Studs [Plain] Black Part 88646 Element 6076678 or 4571146 ×3
  • Plate Special 4 x 4, Studs on One Edge Plain] Black Part 6179 Element 617926 ×4
  • Plate Special 4 x 6, Studs on 3 Edges Black Part 6180 Element 4100378 or 618026 ×1
  • Pneumatic T-Piece (T Bar) [New Style] Black Part 4697b Element 6104209 1 spare in the box ×1
  • Technic Axle 2 Notched Black Part 32062 Element 4109810 or 3206226 ×8
  • Technic Axle 8 Black Part 3707 Element 370726 ×1
  • Technic Brick 1 x 4 [3 Pin Holes] Black Part 3701 Element 370126 ×4
  • Technic Pin with Friction Ridges Lengthwise and Center Slots Black Part 2780 Element 4121715 or 278026 1 spare in the box ×6
  • Tile 1 x 1 with Groove Black Part 3070b Element 307026 1 spare in the box ×2
  • Tile 1 x 3 Black Part 63864 Element 4558170 ×8
  • Tile 1 x 4 with Groove Black Part 2431 Element 243126 ×2
  • Tile 2 x 3 Black Part 26603 Element 6162892 ×4
  • Tile 2 x 4 with Groove Black Part 87079 Element 4560182 ×6

Light Bluish Gray 58 pieces

  • Bracket 1 x 1 - 1 x 1 Light Bluish Gray Part 36841 Element 6248078 or 6227012 ×7
  • Brick Curved Inverted 2 x 2 x 2/3 Light Bluish Gray Part 32803 Element 6185676 ×2
  • Hinge Cylinder 1 x 2 Locking with 1 Finger and Axle Hole On Ends Light Bluish Gray Part 30552 Element 4211679 ×5
  • Hinge Plate 1 x 2 Locking with 1 Finger on Side, without Groove Light Bluish Gray Part 44567b Element 6266251 ×2
  • Hinge Plate 1 x 2 Locking with 2 Fingers on Side, 9 Teeth Light Bluish Gray Part 60471 Element 4515341 ×3
  • Plate Special 1 x 2 5.9mm Centre Side Towball Socket Light Bluish Gray Part 14704 Element 6414561 or 6338165 ×1
  • Plate Special 1 x 2 5.9mm Towball Socket Light Bluish Gray Part 14418 Element 6414556 or 6338163 ×6
  • Plate Special 1 x 2 with Clips Horizontal [Open O Clips] Light Bluish Gray Part 60470b Element 6337268 or 4556157 ×1
  • Plate Special 1 x 2 with Handle on End [Closed Ends] Light Bluish Gray Part 60478 Element 4515369 ×1
  • Technic Pin 1/2 without Friction Ridges Light Bluish Gray Part 4274 Element 4274194 or 4211483 1 spare in the box ×26
  • Tile 2 x 2 with Groove Light Bluish Gray Part 3068b Element 4211413 ×1
  • Tile Round 1 x 1 Light Bluish Gray Part 98138 Element 6284071 or 4650260 1 spare in the box ×2
  • Wedge Plate 4 x 4 with 2 x 2 Cutout Light Bluish Gray Part 43719 Element 6275406 or 6093960 ×1

Tan 55 pieces

  • Animal / Creature Accessory, Horse Hitching, 1 x 2 Plate and 2 x 2 Plate [Studded] Tan Part 2397 Element 6287596 or 4260925 ×2
  • Bracket 1 x 2 - 1 x 2 Tan Part 99781 Element 6249809 or 6092684 ×1
  • Bracket 1 x 2 - 2 x 2 Inverted Tan Part 99207 Element 6174925 ×2
  • Brick Special 1 x 1 with Studs on 2 Sides Tan Part 47905 Element 4213568 ×2
  • Plate 1 x 3 Tan Part 3623 Element 4121921 or 362305 ×3
  • Plate 1 x 6 Tan Part 3666 Element 4124067 or 366605 ×4
  • Plate 2 x 2 Tan Part 3022 Element 4114084 or 302205 ×10
  • Plate 2 x 2 Corner Tan Part 2420 Element 4114077 or 242005 ×4
  • Plate 2 x 3 Tan Part 3021 Element 4118790 or 302105 ×1
  • Plate 2 x 6 Tan Part 3795 Element 4113993 or 379505 ×1
  • Plate 2 x 8 Tan Part 3034 Element 4113988 or 303405 ×1
  • Plate Round 1 x 1 with Solid Stud Tan Part 6141 Element 4161734 or 614105 1 spare in the box ×3
  • Plate Special 1 x 2 [Side Handle Closed Ends] Tan Part 48336 Element 4217562 ×3
  • Plate Special 1 x 2 with Clip Horizontal on Side Tan Part 11476 Element 6313119 or 6177314 ×1
  • Technic Axle Pin without Friction Ridges Lengthwise Tan Part 3749 Element 4666579 or 4186017 ×16
  • Tile 2 x 2 with Groove Tan Part 3068b Element 4185177 or 4114002 ×1

Blue 29 pieces

  • Brick 2 x 10 Blue Part 3006 Element 4615600 or 300623 ×1
  • Brick 2 x 4 Blue Part 3001 Element 300173 or 300123 ×1
  • Technic Axle Pin with Friction Ridges Lengthwise Blue Part 43093 Element 4309323 or 4206482 ×3
  • Technic Pin 1/2 without Friction Ridges Blue Part 4274 Element 4143005 1 spare in the box ×12
  • Technic Pin Long with Friction Ridges Lengthwise, 2 Center Slots Blue Part 6558 Element 4514553 ×12

Dark Bluish Gray 20 pieces

  • Plate 1 x 1 Dark Bluish Gray Part 3024 Element 4210719 1 spare in the box ×2
  • Plate 1 x 2 Dark Bluish Gray Part 3023 Element 4211063 Also in Black ×2
  • Plate Special 1 x 2 with 5.9mm Centre Side Towball Dark Bluish Gray Part 14417 Element 6414560 or 6338160 ×2
  • Plate Special 1 x 2 with 5.9mm Towball Socket and Towball Dark Bluish Gray Part 14419 Element 6414554 or 6338166 ×3
  • Plate Special 1 x 2 with End Towball Dark Bluish Gray Part 22890 Element 6370802 or 6338168 ×5
  • Technic Axle 4 with Stop Dark Bluish Gray Part 87083 Element 6083620 or 4560177 ×6

Reddish Brown 13 pieces

  • Book Binding with Two Studs Reddish Brown Part 24324 Element 6167879 or 6134672 ×1
  • Book Cover [Plain] Reddish Brown Part 24093 Element 6174229 or 6134673 ×1
  • Plate 1 x 1 Reddish Brown Part 3024 Element 4221744 1 spare in the box ×2
  • Plate 1 x 2 Reddish Brown Part 3023 Element 4211150 ×5
  • Tile 1 x 2 with Groove Reddish Brown Part 3069b Element 4211151 ×1
  • Tile 2 x 4 with Groove Reddish Brown Part 87079 Element 4579690 ×3

Red 7 pieces

  • Equipment Cup / Mug [Plain] Red Part 3899 Element 389921 ×1
  • Technic Brick 1 x 2 with Axle Hole Type 1 [+ Opening] and Bottom Pin Red Part 32064a Element 6196217 or 4513987 ×2
  • Technic Brick 1 x 4 [3 Pin Holes] Red Part 3701 Element 370121 ×4

Green 5 pieces

  • Brick 2 x 2 Green Part 3003 Element 300328 ×1
  • Technic Brick 1 x 2 with Axle Hole Type 1 [+ Opening] and Bottom Pin Green Part 32064a Element 6206248 or 4233489 ×4

Dark Tan 4 pieces

  • Bracket 1 x 2 - 2 x 2 Dark Tan Part 44728 Element 6275485 ×3
  • Tile 1 x 2 with Groove Dark Tan Part 3069b Element 4496699 ×1

Lime 4 pieces

  • Technic Brick 1 x 4 [3 Pin Holes] Lime Part 3701 Element 6132373 or 4166527 ×4

Yellow 3 pieces

  • Brick 1 x 4 Yellow Part 3010 Element 301024 ×1
  • Brick 2 x 2 Yellow Part 3003 Element 4103588 or 300374 ×2

Flat Silver 2 pieces

  • Tool Hammer Cross Pein [3-Rib Handle] Flat Silver Part 604547 ×1
  • Tool Screwdriver with Wide Head [3-Rib Handle] Flat Silver Part 604550 ×1

Orange 2 pieces

  • Brick 2 x 3 Orange Part 3002 Element 4153826 or 4125971 ×2

Dark Turquoise 1 piece

  • Brick and Axle Separator v2.0 Dark Turquoise Part 96874 Element 6254100 ×1

Medium Nougat 1 piece

  • Box / Crate with Handholds 3 x 4 x 1 2/3 Medium Nougat Part 30150 Element 6035734 ×1

Trans-Clear 1 piece

  • Brick 2 x 2 without Inside Ridges Trans-Clear Part 6223 Element 6514093 or 6239418 ×1

[No Color/Any Color] 1 piece

  • Sticker Sheet for Set 21320-1 [No Color/Any Color] Part 68493 Element 6305368 ×1

Minifigures 2 figures

  • Paleontologist Minifigure, checked as a whole figure ×1
  • Skeleton, Standard Face, Fedora Minifigure, checked as a whole figure ×1

Tick each piece as you find it, or mark it missing.

When a piece really is missing

Ask LEGO

LEGO takes requests for pieces missing from a new set through its customer service site. The form asks for the set number and each piece's element ID, the number printed beside the piece in the parts list at the back of the instructions. This checker lists both.

Request a replacement from LEGO

Buy the piece

Mark a piece missing and your list links it to an eBay search for that part, which also covers pieces from older or second-hand sets.

Keep a record

Copy or download your missing list (the CSV opens in any spreadsheet), or print the whole checklist and tick pieces off on paper. Your marks stay in this browser, so you can check a big set over several sittings.