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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.

Magic Flash

Checking

5581 Magic Flash

787 pieces in 229 part and color combinations.

LEGO counts 784 pieces. This inventory comes from a separate parts catalog and lists 787; 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.

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Piece checklist

Black 352 pieces

  • Bar 8L - Two Stop Rings / One Pin, Technic Figure Ski Pole [Rounded End] Black Part 2714a Element 4120251 ×1
  • Bracket 1 x 2 - 1 x 4 [Square Corners] Black Part 2436 Element 4282746 or 243626 ×3
  • Brick 1 x 1 Black Part 3005 Element 300526 ×10
  • Brick 1 x 16 Black Part 2465 Element 246576 or 246526 ×2
  • Brick 1 x 2 Black Part 3004 Element 300426 ×7
  • Brick 1 x 3 Black Part 3622 Element 362226 ×2
  • Brick 1 x 4 with Bottom Tubes, Lowered Center Cross Support Black Part 3010a ×2
  • Brick 1 x 6 with Bottom Tubes and 2 Lowered Cross Supports Black Part 3009b ×2
  • Brick 1 x 8 with Bottom Tubes and 3 Lowered Cross Supports Black Part 3008b ×2
  • Brick 2 x 2 Black Part 3003 Element 4103587 or 300326 ×2
  • Brick 2 x 2 Corner Black Part 2357 Element 235776 or 235726 ×2
  • Brick 2 x 3 Black Part 3002 Element 300226 ×1
  • Brick 2 x 8 Black Part 3007 Element 6037390 or 300726 ×2
  • Brick Curved 1 x 2 x 1 1/3 with Curved Top Black Part 6091 Element 6383142 or 6184784 ×2
  • Brick Sloped 33° 3 x 1 Black Part 4286 Element 428626 ×4
  • Brick Sloped 33° 3 x 4 Black Part 3297 Element 6435854 or 329726 ×1
  • Brick Sloped 45° 2 x 1 with Bottom Pin Black Part 3040b Element 4121966 or 304026 ×8
  • Brick Sloped 45° 2 x 1 with Bottom pin, with 9 Large + 3 Small White Buttons Print Black Part 3040bpr0011 Element 4251811 or 4121975 ×3
  • Brick Sloped 45° 2 x 2 Double Convex Black Part 3045 Element 4189064 or 304526 ×2
  • Brick Sloped 45° 2 x 2 with 3 Gauges and 3 Knobs Print Black Part 3039pr9970 Element 4251812 or 4163777 ×1
  • Brick Sloped 45° 2 x 3 Black Part 3038 Element 303826 ×2
  • Brick Sloped 75° 2 x 1 x 3 with Open Stud Black Part 4460a ×2
  • Brick Sloped Inverted 33° 3 x 2, No Connections between Studs, Ovoid Bottom Pin Black Part 3747a ×3
  • Brick Sloped Inverted 34° 3 x 1 without Internal Stopper Black Part 4287a ×6
  • Brick Sloped Inverted 45° 2 x 1 Black Part 3665 Element 366526 ×6
  • Brick Sloped Inverted 45° 2 x 2 [Ovoid Bottom Pin, Bar-sized Stud Holes] Black Part 3660 Element 366026 ×7
  • Brick Sloped Inverted 45° 4 x 2 Double with 2 x 2 Recessed Black Part 4871 Element 4188534 or 487126 ×2
  • Brick Special 1 x 1 with Handle Black Part 2921 Element 6170566 or 292126 ×4
  • Brick Special 1 x 1 with Headlight Black Part 4070 Element 407026 ×2
  • Brick Wedged, Sloped Inverted 4 x 4 Triple [2 Connections between Front Studs] Black Part 4855 Element 4550004 or 4278249 ×2
  • Door 1 x 4 x 5 Train Left with Yellow Stripe Print Black Part 4181pr0007 ×1
  • Door 1 x 4 x 5 Train Right with Yellow Stripe Print Black Part 4182pr0007 ×1
  • Hinge Brick 1 x 2 Base Black Part 3937 Element 393726 ×1
  • Hinge Brick 1 x 2 Top Plate Thin Black Part 3938 Element 393826 ×1
  • Hinge Tile 1 x 4 Black Part 4625 Element 4280138 or 462526 ×3
  • Hinge Train Gate 2 x 4 Black Part 2873 Element 4257363 or 4163971 ×2
  • Hinge Vehicle Roof 4 x 4 Black Part 4213 Element 421326 ×3
  • Hinge Vehicle Roof Holder 1 x 4 Black Part 4315 Element 4250225 or 431576 ×2
  • Panel 1 x 2 x 2 [Solid Studs] Black Part 4864a Element 4113021 ×2
  • Plate 1 x 1 Black Part 3024 Element 302426 1 spare in the box ×17
  • Plate 1 x 10 Black Part 4477 Element 447726 ×8
  • Plate 1 x 2 Black Part 3023 Element 302326 ×30
  • Plate 1 x 3 Black Part 3623 Element 362326 ×17
  • Plate 1 x 4 Black Part 3710 Element 371026 ×12
  • Plate 1 x 6 Black Part 3666 Element 366626 ×7
  • Plate 1 x 8 Black Part 3460 Element 346026 ×3
  • Plate 2 x 10 Black Part 3832 Element 383226 ×1
  • Plate 2 x 12 Black Part 2445 Element 244526 ×2
  • Plate 2 x 2 Black Part 3022 Element 302226 ×11
  • Plate 2 x 2 Corner Black Part 2420 Element 242026 ×14
  • Plate 2 x 3 Black Part 3021 Element 302126 ×6
  • Plate 2 x 4 Black Part 3020 Element 302026 ×10
  • Plate 2 x 6 Black Part 3795 Element 379526 ×3
  • Plate 2 x 8 Black Part 3034 Element 303426 ×8
  • Plate 4 x 10 Black Part 3030 Element 303076 or 303026 ×3
  • Plate 4 x 6 Black Part 3032 Element 303226 ×2
  • Plate 6 x 10 Black Part 3033 Element 303326 ×3
  • Plate 6 x 8 Black Part 3036 Element 303676 or 303626 ×1
  • Plate Round 1 x 1 with Solid Stud Black Part 6141 Element 614126 1 spare in the box ×4
  • Plate Special 1 x 1 with Clip Horizontal [Thick U Clip] Black Part 6019 Element 601976 or 601926 ×2
  • Plate Special 1 x 1 with Clip Light, Bar Hole [Thick Ring] Black Part 4081b Element 6281993 or 4632571 ×2
  • Plate Special 1 x 1 with Clip Vertical [Thick U Clip] Black Part 4085c Element 408526 ×4
  • Plate Special 1 x 2 Side Handle [Free Ends] Black Part 2540 Element 4140588 or 254026 ×2
  • Plate Special 1 x 2 with 1 Stud without Groove (Jumper) Black Part 3794a ×4
  • Plate Special 1 x 2 with Bar Up [Horizontal Arm 6mm] Black Part 4623 Element 4597267 or 462326 ×2
  • Plate Special 1 x 2 with Ladder Black Part 4175 Element 6285241 or 6179557 ×2
  • Plate Special 1 x 2 with Long Towball Black Part 2508 Element 4274405 or 250826 ×1
  • Propeller 3 Blade 3 Diameter with Axle Cross Black Part 6041 Element 604126 ×1
  • Technic Axle 10 Black Part 3737 Element 373726 ×2
  • Technic Axle 12 Black Part 3708 Element 370826 ×1
  • Technic Axle 2 Black Part 3704 Element 370426 ×2
  • Technic Axle 4 Black Part 3705 Element 370526 ×1
  • Technic Axle 6 Black Part 3706 Element 370626 ×2
  • Technic Brick 1 x 2 [1 Pin Hole] Black Part 3700 Element 370026 ×2
  • Technic Brick 1 x 4 [3 Pin Holes] Black Part 3701 Element 370126 ×1
  • Technic Brick 1 x 6 [5 Pin Holes] Black Part 3894 Element 389426 ×2
  • Technic Pin with Friction Ridges Lengthwise and Center Slots Black Part 2780 Element 4121715 or 278026 1 spare in the box ×5
  • Technic Plate 2 x 8 [7 Holes] Black Part 3738 Element 373826 ×1
  • Tile 1 x 2 with Groove Black Part 3069b Element 306926 ×11
  • Tile 1 x 4 with Groove Black Part 2431 Element 243126 ×4
  • Tile 1 x 8 with Groove Black Part 4162 Element 416226 ×3
  • Tile 2 x 2 with Groove Black Part 3068b Element 306826 ×1
  • Tile Special 1 x 1 with Clip and Straight Tips Black Part 2555 Element 255526 ×2
  • Tyre 24 x 13 Model Team Black Part 2696 Element 269676 or 269626 ×5
  • Tyre 30 x 10.5 Offset Tread Black Part 2346 Element 234676 or 234626 ×4
  • Wedge Plate 3 x 6 Cut Corners Black Part 2419 Element 241926 ×4
  • Wedge Plate 8 x 4 Wing Left Black Part 3933 Element 4189089 or 393326 ×1
  • Wedge Plate 8 x 4 Wing Right with Stud Notch Black Part 3934 Element 4189090 or 393426 ×1
  • Window 1 x 4 x 3 Train with All Studs Hollow Black Part 4033 Element 4295755 or 403326 ×2
  • Wing, Tail 4 x 1 x 3 Black Part 2340 Element 6591863 or 4651541 ×2

Light Gray 232 pieces

  • Antenna 1 x 4 with Rounded Top Light Gray Part 3957a Element 395702 ×6
  • Antenna 8H Whip Light Gray Part 2569 Element 4188299 or 256902 ×3
  • Bar 1 x 6 [Closed Studs] Light Gray Part 6140 Element 614002 ×2
  • Bar 8L - Two Stop Rings / One Pin, Technic Figure Ski Pole [Rounded End] Light Gray Part 2714a Element 4195002 or 271402 ×1
  • Brick 1 x 1 x 5 with Blocked Open or Hollow Stud Light Gray Part 2453a ×2
  • Brick 1 x 2 Light Gray Part 3004 Element 300402 ×2
  • Brick 2 x 4 Light Gray Part 3001 Element 4116259 or 300102 ×1
  • Brick 2 x 8 Light Gray Part 3007 Element 300702 ×1
  • Brick Curved 1 x 2 x 1 1/3 with Curved Top Light Gray Part 6091 Element 609102 ×6
  • Brick Round 1 x 1 Open Stud Light Gray Part 3062b Element 306202 ×17
  • Brick Sloped 45° 2 x 1 with Bottom Pin Light Gray Part 3040b Element 4121933 or 304002 ×6
  • Brick Sloped Inverted 45° 3 x 1 Double with 2 Completely Open Studs Light Gray Part 2341 Element 234102 ×2
  • Brick Special 1 x 1 with Headlight Light Gray Part 4070 Element 407002 ×14
  • Brick Special 1 x 2 with Pin Light Gray Part 2458 Element 245802 ×2
  • Equipment Weapon, Loudhailer / Speaker / Blaster / Space Gun Light Gray Part 4349 Element 434902 ×6
  • Hinge Brick 1 x 2 Base Light Gray Part 3937 Element 393702 ×2
  • Hinge Brick 1 x 2 Top Plate Thin Light Gray Part 3938 Element 393802 ×4
  • Hinge Plate 1 x 2 with 2 Fingers and Hollow Studs Light Gray Part 4276b Element 427602 ×1
  • Hinge Plate 1 x 2 with 3 Fingers On Side Light Gray Part 2452 Element 4238280 or 245202 ×1
  • Lever Small Base with Light Gray Lever Light Gray Part 298c03 Element 73777 1 spare in the box ×3
  • Plate 1 x 1 Light Gray Part 3024 Element 302402 ×2
  • Plate 1 x 10 Light Gray Part 4477 Element 447702 ×2
  • Plate 1 x 2 Light Gray Part 3023 Element 302302 ×7
  • Plate 1 x 3 Light Gray Part 3623 Element 362302 ×4
  • Plate 1 x 4 Light Gray Part 3710 Element 371002 ×2
  • Plate 1 x 6 Light Gray Part 3666 Element 366602 ×7
  • Plate 1 x 8 Light Gray Part 3460 Element 346002 ×1
  • Plate 2 x 2 Light Gray Part 3022 Element 302202 ×5
  • Plate 2 x 2 Corner Light Gray Part 2420 Element 242052 or 242002 ×4
  • Plate 2 x 6 Light Gray Part 3795 Element 379502 ×6
  • Plate 4 x 4 Light Gray Part 3031 Element 4243813 or 303102 ×1
  • Plate 4 x 8 Light Gray Part 3035 Element 303502 ×1
  • Plate 6 x 8 Light Gray Part 3036 Element 303652 or 303602 ×2
  • Plate Round 1 x 1 with Solid Stud Light Gray Part 6141 Element 614102 1 spare in the box ×8
  • Plate Round 2 x 2 with Rounded Bottom [Boat Stud] Light Gray Part 2654 Element 265402 ×4
  • Plate Special 1 x 1 with Clip Horizontal [Thick U Clip] Light Gray Part 6019 Element 601952 or 601902 ×10
  • Plate Special 1 x 1 with Clip Light, Bar Hole [Thick Ring] Light Gray Part 4081b Element 408102 ×4
  • Plate Special 1 x 2 with 1 Stud without Groove (Jumper) Light Gray Part 3794a Element 379402 ×3
  • Plate Special 1 x 2 with Ladder Light Gray Part 4175 Element 4100526 or 417502 ×5
  • Plate Special 2 x 2 with Towball Socket, Short, 4 Slots Light Gray Part 3730 Element 373002 ×1
  • Tap 1 x 1 with Hole in Spout Light Gray Part 4599a Element 459902 ×2
  • Technic Axle Pin without Friction Ridges Lengthwise Light Gray Part 3749 Element 4184168 or 4154179 1 spare in the box ×3
  • Technic Axle and Pin Connector Light Gray Part 3651 Element 4105243 or 365102 ×2
  • Technic Axle and Pin Connector Toggle Joint Toothed [with Slots] Light Gray Part 4273b Element 427302 ×1
  • Technic Brick 1 x 16 [15 Pin Holes] Light Gray Part 3703 Element 370302 ×4
  • Technic Brick 1 x 6 [5 Pin Holes] Light Gray Part 3894 Element 389402 ×1
  • Technic Bush Light Gray Part 3713 Element 4125313 or 659002 1 spare in the box ×7
  • Technic Bush 1/2 Toothed Type I [+ Opening] Light Gray Part 4265a Element 426502 1 spare in the box ×1
  • Technic Gear 14 Tooth Bevel Light Gray Part 4143 Element 414352 or 414302 ×2
  • Technic Gear 8 Tooth Light Gray Part 3647 Element 364702 ×2
  • Technic Gear Rack 1 x 4 Light Gray Part 3743 Element 374302 ×1
  • Technic Pin 1/2 without Friction Ridges Light Gray Part 4274 Element 427402 1 spare in the box ×3
  • Technic Pin without Friction Ridges Lengthwise Light Gray Part 3673 Element 4184166 or 367302 1 spare in the box ×3
  • Technic Plate 1 x 8 with Toothed Ends Light Gray Part 4442 Element 444252 or 444202 ×3
  • Technic Plate 2 x 4 [3 Holes] Light Gray Part 3709 Element 370902 ×1
  • Technic Steering Arm Light Gray Part 4261 Element 4225506 or 4189316 ×2
  • Technic Steering Wheel Small (3 Studs Diameter) Light Gray Part 2819 Element 4113032 or 281902 ×1
  • Technic Universal Joint 4L [Complete Assembly] Light Gray Part 9244 Element 9244 ×1
  • Technic Wedge Belt Wheel [aka Pulley] Light Gray Part 4185 Element 4100502 or 418502 ×1
  • Tile 1 x 1 with Groove Light Gray Part 3070b Element 307052 or 307002 1 spare in the box ×2
  • Tile 1 x 4 with Groove Light Gray Part 2431 Element 243102 ×2
  • Tile 1 x 8 with Groove Light Gray Part 4162 Element 416202 ×4
  • Tile Special 1 x 1 with Clip and Straight Tips Light Gray Part 2555 Element 255502 ×6
  • Tile Special 1 x 2 Grille with Bottom Groove Light Gray Part 2412b Element 241202 ×3
  • Weapon Gun / Torch (Space) [with Grooves] Light Gray Part 3959 Element 4254948 or 395952 ×2
  • Weapon Lance Light Gray Part 3849 Element 4213223 or 4189054 ×2
  • Wheel 30 x 13 Model Team Light Gray Part 2695 Element 4141535 or 269502 ×5
  • Wheel with Split Axle hole Light Gray Part 3482 Element 348202 ×4

Red 88 pieces

  • Bar 6.6L with Stop Ring [Umbrella Stand] Red Part 4095 Element 4143125 or 409571 ×1
  • Brick 1 x 1 Red Part 3005 Element 300521 ×2
  • Brick 1 x 2 Red Part 3004 Element 4613961 or 300421 ×2
  • Brick Sloped 33° 3 x 1 Red Part 4286 Element 428621 ×2
  • Brick Sloped 45° 2 x 1 with Bottom Pin Red Part 3040b Element 4121934 or 304021 ×1
  • Brick Sloped 75° 2 x 1 x 3 with Open Stud Red Part 4460a Element 446021 ×2
  • Brick Special 1 x 1 with Headlight Red Part 4070 Element 407021 ×2
  • Hinge Plate 1 x 2 with 2 Fingers and Hollow Studs Red Part 4276b Element 4238277 or 427621 ×2
  • Hinge Plate 1 x 2 with 3 Fingers [Hollow Studs] Red Part 4275b Element 4179194 or 427521 ×4
  • Hinge Tile 1 x 2 1/2 with 2 Fingers on Top Red Part 4531 Element 453121 ×2
  • Panel 1 x 2 x 1 [Square Corners] Red Part 4865a ×1
  • Panel 1 x 2 x 2 [Solid Studs] Red Part 4864a ×1
  • Plate 1 x 1 Red Part 3024 Element 302421 ×6
  • Plate 1 x 10 Red Part 4477 Element 447721 ×3
  • Plate 1 x 2 Red Part 3023 Element 302321 ×22
  • Plate 1 x 3 Red Part 3623 Element 362321 ×2
  • Plate 1 x 4 Red Part 3710 Element 371021 ×4
  • Plate 1 x 6 Red Part 3666 Element 366621 ×5
  • Plate 1 x 8 Red Part 3460 Element 346021 ×3
  • Plate 2 x 2 Red Part 3022 Element 4613974 or 302221 ×3
  • Plate 2 x 2 Corner Red Part 2420 Element 242071 or 242021 ×4
  • Plate 2 x 3 Red Part 3021 Element 302121 ×5
  • Plate 2 x 4 Red Part 3020 Element 302021 ×1
  • Plate 2 x 8 Red Part 3034 Element 303421 ×2
  • Plate 4 x 10 Red Part 3030 Element 4535164 or 4188302 ×1
  • Plate Special 1 x 1 with Clip Vertical [Thick U Clip] Red Part 4085c Element 408521 ×1
  • Steering Stand 1 x 2 with Black Steering Wheel Red Part 3829c01 Element 9552 ×1
  • Tile 1 x 4 with Groove Red Part 2431 Element 243121 ×1
  • Tile 2 x 2 with Groove Red Part 3068b Element 306821 ×1
  • Wedge Plate 3 x 6 Cut Corners Red Part 2419 Element 241921 ×1

Yellow 62 pieces

  • Brick 1 x 1 Yellow Part 3005 Element 300524 ×4
  • Brick 1 x 2 Yellow Part 3004 Element 4613966 or 300424 ×6
  • Brick 1 x 4 with Bottom Tubes, Lowered Center Cross Support Yellow Part 3010a ×2
  • Brick Round Corner 2 x 2 Macaroni with Stud Notch Yellow Part 3063b Element 306324 ×2
  • Brick Sloped 45° 2 x 2 Yellow Part 3039 Element 303924 ×2
  • Brick Sloped 75° 2 x 2 x 3 [Hollow Studs] Yellow Part 3684 Element 4248062 or 4189348 ×2
  • Brick Special 1 x 1 with Headlight Yellow Part 4070 Element 407024 ×8
  • Plate 1 x 1 Yellow Part 3024 Element 302424 Also in Trans-Yellow ×2
  • Plate 1 x 2 Yellow Part 3023 Element 302324 ×8
  • Plate 1 x 3 Yellow Part 3623 Element 362324 ×6
  • Plate 1 x 6 Yellow Part 3666 Element 366624 ×3
  • Plate 1 x 8 Yellow Part 3460 Element 346024 ×4
  • Plate 2 x 10 Yellow Part 3832 Element 383224 ×1
  • Plate 2 x 2 Yellow Part 3022 Element 4613978 or 302224 ×4
  • Plate Special 1 x 2 Side Handle [Free Ends] Yellow Part 2540 Element 4140587 or 254024 ×2
  • Technic Plate 2 x 4 [3 Holes] Yellow Part 3709 Element 370924 ×1
  • Tile 1 x 2 with Groove Yellow Part 3069b Element 306924 ×2
  • Tile Special 1 x 2 Grille with Bottom Groove Yellow Part 2412b Element 241224 ×2
  • Wedge Plate 3 x 6 Cut Corners Yellow Part 2419 Element 6207376 or 241924 ×1

Trans-Yellow 12 pieces

  • Plate 1 x 1 Trans-Yellow Part 3024 Element 6513966 or 6252045 Also in Yellow ×6
  • Plate Round 1 x 1 with Solid Stud Trans-Yellow Part 6141 Element 6514056 or 6240216 1 spare in the box ×4
  • Tile 1 x 1 with Groove Trans-Yellow Part 3070b Element 6636668 or 6088721 1 spare in the box ×2

Blue 10 pieces

  • Brick 1 x 4 Blue Part 3010 Element 301023 ×1
  • Hinge Brick 1 x 2 Base Blue Part 3937 Element 393723 ×2
  • Plate 1 x 2 Blue Part 3023 Element 302323 ×3
  • Plate 1 x 3 Blue Part 3623 Element 362323 ×2
  • Tap 1 x 1 with Hole in Spout Blue Part 4599a Element 4279385 ×2

Trans-Light Blue 10 pieces

  • Glass for Train Door Lip On Top and Bottom Trans-Light Blue Part 4183 Element 6074032 or 418342 ×2
  • Glass for Train Window 1 x 4 x 3 Trans-Light Blue Part 4034 Element 403442 ×2
  • Panel 1 x 4 x 3 [Solid Studs] Trans-Light Blue Part 4215a ×4
  • Windscreen 3 x 10 x 3 Trans-Light Blue Part 2694 ×1
  • Windscreen 3 x 4 x 1 1/3 with 2 Studs on Top Trans-Light Blue Part 2437 Element 6507914 or 6253361 ×1

White 8 pieces

  • Bar 1 x 8 x 2 White Part 2486 Element 248601 ×1
  • Plate 1 x 2 White Part 3023 Element 6552100 or 6548261 ×1
  • Plate Special 1 x 1 with Clip Horizontal [Thick U Clip] White Part 6019 Element 601951 or 601901 ×2
  • Tile Special 1 x 1 with Clip and Straight Tips White Part 2555 Element 255501 ×4

Trans-Clear 6 pieces

  • Brick 1 x 2 without Bottom Tube Trans-Clear Part 3065 Element 6514262 or 6244904 ×2
  • Plate Round 1 x 1 with Solid Stud Trans-Clear Part 6141 Element 6514052 or 6240030 1 spare in the box ×4

Trans-Red 6 pieces

  • Plate Round 1 x 1 with Solid Stud Trans-Red Part 6141 Element 6514051 or 6208450 1 spare in the box ×2
  • Tile 1 x 1 with Groove Trans-Red Part 3070b Element 6581817 or 6254248 1 spare in the box ×4

[No Color/Any Color] 1 piece

  • Sticker Sheet for Set 5581-1 [No Color/Any Color] Part 821437 Element 821437 ×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.