BlockTalk Find Your Set

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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.

Steam Locomotive

Checking

721 Steam Locomotive

115 pieces in 30 part and color combinations.

LEGO counts 126 pieces. This inventory comes from a separate parts catalog and lists 115; 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.

Show

Piece checklist

Black 74 pieces

  • Brick 1 x 1 Black Part 3005 Element 300526 ×6
  • Brick 1 x 2 Black Part 3004 Element 300426 ×9
  • Brick 1 x 4 Black Part 3010 Element 301026 ×8
  • Brick 1 x 6 Black Part 3009 Element 300926 ×3
  • Brick 1 x 8 Black Part 3008 Element 300826 ×2
  • Brick 1 x 8 with Gold '721' Print Black Part 3008pr0013 ×2
  • Brick 2 x 2 without Inside Ridges Black Part 3003a ×1
  • Brick 2 x 4 without Cross Supports Black Part 3001a ×2
  • Brick 2 x 4, 12V with Power Pickups for Train Motor and Solid Pins Black Part 433c01 ×2
  • Brick Round 1 x 1 Solid Stud Black Part 3062a ×5
  • Brick Sloped 45° 2 x 1 without Bottom Pin Black Part 3040a ×2
  • Brick Sloped 45° 2 x 2 Black Part 3039 Element 303926 ×1
  • Brick Sloped 45° 2 x 4 Black Part 3037 Element 303726 ×8
  • Motor, Train, 12V 12 x 4 x 3 1/3 Type I with Two Side Holes Black Part upn0274c02 ×1
  • Plate 1 x 2 Black Part 3023 Element 302326 ×3
  • Plate 2 x 2 Black Part 3022 Element 302226 ×4
  • Plate 2 x 3 Black Part 3021 Element 302126 ×5
  • Plate 2 x 4 Black Part 3020 Element 302026 ×8
  • Train Brick 2 x 4 x 1 1/3 Sliding Wheel Block - Type A Black Part upn0184 ×2

Red 32 pieces

  • Plate 1 x 2 Red Part 3023 Element 302321 ×12
  • Plate 2 x 2 Red Part 3022 Element 4613974 or 302221 ×1
  • Plate 2 x 3 Red Part 3021 Element 302121 ×6
  • Plate 2 x 4 Red Part 3020 Element 302021 ×3
  • Train Wheel Spoked for Motor Red Part upn0383a ×8
  • Window 1 x 1 x 1 Classic with Long Sill [Complete] Red Part 3087bc01 ×2

Light Gray 5 pieces

  • Tyre for Train Wheel for Electric Train Motor 12V Light Gray Part 458 ×4
  • Vehicle Base, Train 6 x 22 Type 1 Motor Opening Light Gray Part 303 ×1

Trans-Clear 2 pieces

  • Brick 1 x 1 Trans-Clear Part 3005 Element 6514207 or 6220959 ×2

Metal 1 piece

  • Screwdriver with Old LEGO Logo [Metal] Metal Part 299 ×1

Yellow 1 piece

  • Plate 2 x 2 Yellow Part 3022 Element 4613978 or 302224 ×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.

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