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.

Master Mechanic Set

Checking

003 Master Mechanic Set

403 pieces in 51 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.

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.

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Piece checklist

White 172 pieces

  • Brick 1 x 1 White Part 3005 Element 6552096 or 6548258 ×14
  • Brick 1 x 2 White Part 3004 Element 6548257 or 4613964 Also in Trans-Clear ×10
  • Brick 2 x 10 White Part 3006 Element 4617855 or 300601 ×3
  • Brick 2 x 2 without Inside Ridges White Part 3003a Also in Trans-Clear ×17
  • Brick 2 x 3 without Cross Supports White Part 3002a ×10
  • Brick 2 x 4 without Cross Supports White Part 3001a Also in Trans-Clear ×90
  • Brick 2 x 8 White Part 3007 Element 6619309 or 6033776 ×2
  • Brick Round Corner 2 x 2 Macaroni with Stud Notch White Part 3063b Element 4501579 or 306301 ×2
  • Brick Special 2 x 4 with Wheel Holder Old, Clear Bottom, Red Inside White Part 7049bc01 ×6
  • Plate 2 x 2 White Part 3022 Element 6552099 or 6548260 ×2
  • Plate 2 x 3 White Part 3021 Element 6550136 or 302101 ×3
  • Plate 2 x 4 White Part 3020 Element 6552098 or 302001 ×4
  • Plate 2 x 8 White Part 3034 Element 6552101 or 303401 ×3
  • Plate 4 x 8 White Part 3035 Element 6609533 or 303501 ×2
  • Plate 6 x 8 White Part 3036 Element 303651 or 303601 ×3
  • Wire 12V / 4.5V with Two Leads [Undetermined Length] White Part 74503 ×1

Red 148 pieces

  • Brick 1 x 1 Red Part 3005 Element 300521 ×13
  • Brick 1 x 2 Red Part 3004 Element 4613961 or 300421 ×14
  • Brick 2 x 10 Red Part 3006 Element 4617857 or 300621 ×3
  • Brick 2 x 2 without Inside Ridges Red Part 3003a ×12
  • Brick 2 x 3 without Cross Supports Red Part 3002a ×10
  • Brick 2 x 4 without Cross Supports Red Part 3001a ×65
  • Brick 2 x 8 Red Part 3007 Element 6036408 or 300721 ×2
  • Brick Round 1 x 1 Solid Stud Red Part 3062a ×2
  • Brick Round Corner 2 x 2 Macaroni with Stud Notch Red Part 3063b Element 306321 ×2
  • Brick Sloped 45° 2 x 2 Red Part 3039 Element 303921 ×4
  • Brick Sloped 45° 2 x 2 Double Red Part 3043 Element 304321 ×1
  • Brick Sloped 45° 2 x 4 Red Part 3037 Element 303721 ×6
  • Brick Sloped 45° 2 x 4 Double Red Part 3041 Element 4144003 or 304121 ×2
  • Wheel Old with 12 Studs Red Part 715 ×4
  • Wheel Old with 4 Studs Red Part 7039 Element 7039 ×8

Blue 22 pieces

  • Battery Box, 4.5V, 8 x 11 x 4 Samsonite Blue Part upn0208 ×3
  • Brick 1 x 1 Blue Part 3005 Element 300523 ×4
  • Brick 1 x 2 Blue Part 3004 Element 4613959 or 300423 ×2
  • Brick 2 x 2 without Inside Ridges Blue Part 3003a ×2
  • Brick 2 x 4 without Cross Supports Blue Part 3001a ×8
  • Motor, 4.5V, 8 x 4 x 3 Samsonite Blue Part upn0209 ×3

Yellow 19 pieces

  • Brick 1 x 1 Yellow Part 3005 Element 300524 ×4
  • Brick 1 x 2 Yellow Part 3004 Element 4613966 or 300424 ×4
  • Brick 2 x 2 without Inside Ridges Yellow Part 3003a ×9
  • Brick 2 x 4 without Cross Supports Yellow Part 3001a ×2

Black 15 pieces

  • Brick 1 x 1 Black Part 3005 Element 300526 ×4
  • Brick 1 x 2 Black Part 3004 Element 300426 ×5
  • Brick 2 x 2 without Inside Ridges Black Part 3003a ×3
  • Brick 2 x 4 without Cross Supports Black Part 3001a ×3

Light Gray 15 pieces

  • Brick 10 x 20 without Bottom Tubes, with '+' Cross Support (early Baseplate) Light Gray Part 700b ×3
  • Tyre Smooth Old Style - Large Light Gray Part 36 ×4
  • Tyre Smooth Old Style - Small Light Gray Part 132a ×8

Trans-Clear 12 pieces

  • Brick 1 x 2 Trans-Clear Part 3004 Element 4256587 or 300410 Also in White ×2
  • Brick 2 x 2 without Inside Ridges Trans-Clear Part 3003a Also in White ×6
  • Brick 2 x 4 without Cross Supports Trans-Clear Part 3001a Also in White ×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.

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