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 Ball Joint with Through Axle HoleBlackPart 53585Element 4286267×4
Energy Effects
2 pieces
Large Figure Weapon Accessory, Flame / Lightning Bolt with Axle Hole with Marbled Trans-Yellow PatternTrans-RedPart 11302pat0001Element 6016236×2
Technic Beams Special
2 pieces
Technic Beam 1 x 3 with Ball Joint in MiddleDark Bluish GrayPart 98577Element 6001085×1
Technic Beam 5 x 5 x 2 Perpendicular Fork 3 FingersDark Bluish GrayPart 19086Element 6102645×1
Technic Bushes
1 piece
Technic BushLight Bluish GrayPart 3713Element 6275844 or 6271817×1
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.