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.

Monorail Accessory Track

Checking

6921 Monorail Accessory Track

46 pieces in 6 part and color combinations.

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.

Show

Piece checklist

Plates 20 pieces

  • Plate 1 x 4 Light Gray Part 3710 Element 371002 ×20

Supports, Girders and Cranes 16 pieces

  • Support 4 x 4 x 5 Stanchion, Tall Studs Black Part 2680 Element 268026 ×8
  • Support 6 x 6 x 10 Stanchion Black Part 2681 Element 268126 ×8

Transportation - Land 10 pieces

  • Vehicle Track, Monorail Curve Long Light Gray Part 2672 ×4
  • Vehicle Track, Monorail Straight Short Light Gray Part 2670 ×2
  • Vehicle Track, Monorail Track Straight Long Light Gray Part 2671 ×4

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.