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.
Technic Axle and Pin Connector Angled #2 - 180°WhitePart 32034Element 6271870 or 4125554×1
Plates
5 pieces
Plate 1 x 1WhitePart 3024Element 6548262 or 3024011 spare in the box×2
Plate 1 x 2WhitePart 3023Element 6552100 or 6548261×3
Bricks Curved
4 pieces
Brick Curved 2 x 2 x 2/3WhitePart 15068Element 6552147 or 6047220×2
Brick Curved 4 x 1 Double, No StudsWhitePart 93273Element 6552143 or 6023806×2
Pneumatics
3 pieces
Pneumatic Hose Connector with Axle ConnectorDark Bluish GrayPart 99021Element 6265669 or 6020189×2
Pneumatic T-Piece (T Bar) [New Style]Light Bluish GrayPart 4697bElement 42115081 spare in the box×1
Projectiles / Launchers
3 pieces
Launcher, Brick Special 1 x 4 Spring Shooter with Light Bluish Gray TopDark Bluish GrayPart 15400Element 6324200 or 6048898×1
Projectile, Spring Shooter Ammunition 8L BarTrans-RedPart 15303Element 6287550 or 6054526×2
Technic Special
3 pieces
Technic Tooth 1 x 3 with Axle Hole [Rounded Underside]Dark Bluish GrayPart 41669Element 6217813×1
Technic Tooth 1 x 3 with Axle Hole [Rounded Underside]WhitePart 41669Element 4173941×2
Plates Special
2 pieces
Plate Special 1 x 2 with Clips Horizontal [Open O Clips]WhitePart 60470bElement 6347287 or 4556152×2
Tiles Special
2 pieces
Tile Special 1 x 1 with Clip with Rounded EdgesWhitePart 15712Element 6348055 or 6054551×2
Bars, Ladders and Fences
1 piece
Bar 3LWhitePart 87994Element 6552205 or 64288031 spare in the box×1
Bricks Round and Cones
1 piece
Cone 1 x 1 [Top Groove]WhitePart 59900Element 6601844 or 4518400×1
Plates Round Curved and Dishes
1 piece
Plate Round 1 x 1 with Solid StudDark Bluish GrayPart 6141Element 42106331 spare in the box×1
Technic Beams Special
1 piece
Technic Beam 1 x 3 with Ball Joint in MiddleDark Bluish GrayPart 98577Element 6001085×1
Technic Bushes
1 piece
Technic Bush 1/2 Smooth with Axle Hole Semi-ReducedLight Bluish GrayPart 32123bElement 6271165 or 42115731 spare in the box×1
Tiles
1 piece
Tile 1 x 2 with GrooveWhitePart 3069bElement 6548264 or 306901×1
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.