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.
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.
Brick Curved 4 x 1 Double, No StudsTan ×1Light Nougat ×2Tan is yellower and darker than Light Nougat.
Brick Curved Inverted 2 x 1Tan ×4Light Nougat ×2Tan is yellower and darker than Light Nougat.
Plate 1 x 2Tan ×2Light Nougat ×2Tan is yellower and darker than Light Nougat.
Plate Round 2 x 2 with Axle Hole Type 1 (+ Opening)Tan ×4Light Nougat ×11Tan is yellower and darker than Light Nougat.
Plate Special 1 x 2 Rounded with 2 Open StudsTan ×7Light Nougat ×8Tan is yellower and darker than Light Nougat.
Plate Special 1 x 3 with 2 Studs with Groove and Inside Stud Holder (Jumper)Tan ×2Light Nougat ×2Tan is yellower and darker than Light Nougat.
3 more look-alike pairs
Tile Special Round 2 x 2 with HoleTan ×2Light Nougat ×4Tan is yellower and darker than Light Nougat.
Technic Wedge Belt Wheel [aka Pulley]Light Bluish Gray ×4Flat Silver ×2Light Bluish Gray is lighter than Flat Silver.
Plate 2 x 2Black ×2Dark Bluish Gray ×6Black is darker than Dark Bluish Gray.
Equipment Cup / TeacupLight Bluish GrayPart 38014Element 6539385×1
Equipment Cup / Teacup Saucer with Recessed Stud on Top [Plain]Light Bluish GrayPart 38799Element 6531935×2
Equipment Flotation Ring [Life Preserver]WhitePart 30340Element 4297083×1
Bars, Ladders and Fences
13 pieces
Bar 1L with Clip [Cut Edges and One Side Hole] [Full Clip]BlackPart 3484Element 6439039×4
Bar 2L with TowballDark Bluish GrayPart 22484Element 6364352 or 6360117×2
Bar Holder with Hole and Bar HandleLight Bluish GrayPart 23443Element 6343976 or 6152107×2
Lever Small Base with Light Bluish Gray LeverLight Bluish GrayPart 298c05Element 6267587 or 4226285×2
Bar 1L with Clip [Cut Edges and One Side Hole] [Full Clip]Reddish BrownPart 3484Element 6439053×2
Bar 3LTanPart 87994Element 6443062×1
Bricks
13 pieces
Brick 1 x 1BlackPart 3005Element 300526×2
Brick 2 x 2Bright PinkPart 3003Element 4550359 or 4245307×1
Brick 1 x 1Light NougatPart 3005Element 6369191 or 4496977×2
Brick 1 x 2OrangePart 3004Element 4613981 or 4121739×1
Brick 1 x 2RedPart 3004Element 4613961 or 300421×1
Brick 1 x 2TanPart 3004Element 4109995 or 300405×4
Brick 1 x 2WhitePart 3004Element 6548257 or 4613964×1
Brick 1 x 3WhitePart 3622Element 6550143 or 362201×1
Wheels and Tyres
13 pieces
Technic Wedge Belt Wheel TireBlackPart 2815Element 6028041 or 281526×2
Tyre 75 x 13BlackPart 7860Element 6619661×2
Technic Wedge Belt Wheel [aka Pulley]Flat SilverPart 4185Element 6533241Also in Light Bluish Gray×2
Technic Wedge Belt Wheel [aka Pulley]Light Bluish GrayPart 4185Element 6321743 or 4494222Also in Flat Silver×4
Wheel 11 x 8 with Center GrooveLight Bluish GrayPart 42610Element 4211758×1
Wheel 56 x13 with SpokesLight Bluish GrayPart 7877Element 6635719×2
Hinges, Arms and Turntables
10 pieces
Hinge Plate 2 x 2 Locking with 1 Finger on TopBlackPart 92582Element 6265730 or 4613759×1
Hinge Plate 1 x 2 Locking with 1 Finger On End, without GrooveDark Bluish GrayPart 44301bElement 6266225×2
Hinge Plate 1 x 2 Locking with 2 Fingers On End, without Groove, 7 TeethDark Bluish GrayPart 54657Element 6267047×2
Hinge Brick 2 x 2 Locking with 2 Fingers Vertical and '+' Axle Hole, 7 TeethLight Bluish GrayPart 53029Element 6263494×1
Hinge Cylinder 1 x 2 Locking with 1 Finger and Axle Hole On Ends [No Side Slots]Light Bluish GrayPart 53923Element 6265704×1
Hinge Plate 2 x 2 Locking with 1 Finger on TopLimePart 92582Element 6529320×1
Hinge Plate 1 x 2 Locking with 2 Fingers on Side, 7 TeethTanPart 50340Element 6338180×1
Hinge Plate 1 x 2 Locking with 2 Fingers on Side, 7 TeethWhitePart 50340Element 6266201×1
Technic Bushes
9 pieces
Technic BushBlackPart 3713Element 6332148 or 6210506×4
Technic Bush 1/2 Smooth with Axle Hole Semi-ReducedBlackPart 32123bElement 6600750×2
Technic Bush 1/2 Smooth with Axle Hole Semi-ReducedLight Bluish GrayPart 32123bElement 6271165 or 4211573×2
Technic Bush 1/2 Smooth with Axle Hole Semi-ReducedYellowPart 32123bElement 6271167 or 3212324×1
Windscreens and Fuselage
5 pieces
Windscreen 6 x 2 x 2 with HandleRedPart 92474Element 6644632×2
Windscreen, Curved 4 x 5RedPart 7613Element 6595576×3
Animal / Creature Body Parts
4 pieces
Animal Body Part, Fin 2 x4 with HandleDark BrownPart 7511Element 6593254×2
Creature Body Part, Horn / Snowman Carrot NoseOrangePart 1756Element 6605295 or 6392921×1
Animal Body Part, Dog Bone [Short]WhitePart 93160Element 6360202 or 4600294×1
Plates Wedged
4 pieces
Wedge Plate 4 x 4 Cut CornerRedPart 30503Element 6278445 or 6065012×2
Wedge Plate 2 x 2 Cut CornerSand BluePart 26601Element 6582286×2
Technic Special
4 pieces
Technic Disc 3 x 3Light Bluish GrayPart 2723Element 4667578×4
Technic Beams
3 pieces
Technic Beam 1 x 9 ThickBlackPart 40490Element 4645732 or 4542788×2
Technic Beam 1 x 2 ThickLight Bluish GrayPart 43857Element 4211862×1
Minifig Upper Body
2 pieces
Arm Mechanical with 2 Clips [Battle Droid]BlackPart 30377Element 6330086 or 4223247×2
Minifig Heads
1 piece
Minifig Head [Plain] [Vented Stud - 2 Holes]BlackPart 28621Element 6454719×1
Minifig Headwear
1 piece
Helmet Round Sphere with Small HoleBlackPart 51283Element 6601565×1
Rock
1 piece
Rock 1 x 1 Jewel / Gem 24 FacetTrans-ClearPart 30153Element 6513976 or 6247798×1
Stickers
1 piece
Sticker Sheet for Set 21371-1[No Color/Any Color]Part 10119087Element 6630722×1
Tools
1 piece
Brick and Axle Separator v2.0OrangePart 96874Element 6240515 or 4654448×1
Tubes and Hoses
1 piece
Hose Rigid 3mm D. 43LFlat SilverPart 75c43Element 6314440×1
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.
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.