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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.

Crystal Crawler

Checking

1728 Crystal Crawler

92 pieces in 36 part and color combinations, plus 1 minifigure.

The piece count includes the 5 parts inside the set's minifigures, which this inventory lists separately. 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.

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Piece checklist

Hinges, Arms and Turntables 21 pieces

  • Arm Grab Jaw Black Part 4221 Element 422126 ×4
  • Arm Holder Brick 1 x 2 with 2 Horizontal Fingers Black Part 30014 Element 3001426 ×2
  • Arm Piece Straight with 2 and 3 Fingers Black Part 3612 Element 610126 ×2
  • Hinge Brick 1 x 2 Base Black Part 3937 Element 393726 ×1
  • Arm Piece 90° Turn [2 / 3 Fingers] Trans-Neon Orange Part 412 Element 3001547 ×4
  • Arm Grab Jaw Holder, 3 Fingers Yellow Part 4220 Element 4107528 or 422024 ×2
  • Arm Piece Straight with 2 and 3 Fingers Yellow Part 3612 Element 610124 ×6

Plates 12 pieces

  • Plate 1 x 10 Yellow Part 4477 Element 6079138 or 6078095 ×2
  • Plate 1 x 6 Yellow Part 3666 Element 366624 ×1
  • Plate 1 x 8 Yellow Part 3460 Element 346024 ×1
  • Plate 2 x 2 Yellow Part 3022 Element 4613978 or 302224 ×4
  • Plate 2 x 2 Corner Yellow Part 2420 Element 242074 or 242024 ×4

Technic Bricks 10 pieces

  • Technic Brick 1 x 2 [1 Pin Hole] Yellow Part 3700 Element 370024 ×10

Bricks Special 8 pieces

  • Bracket 8 x 2 x 1 1/3 Black Part 4732 Element 473226 ×2
  • Brick Special 1 x 2 x 2 1/3 with Spring Unit Black Part 2605c01 Element 74570 ×2
  • Brick Special Octagonal 2 x 2 x 3 1/3 Corner Yellow Part 6043 Element 4247840 or 604324 ×4

Technic Pins 6 pieces

  • Technic Axle Pin without Friction Ridges Lengthwise Light Gray Part 3749 Element 4184168 or 4154179 ×4
  • Technic Pin without Friction Ridges Lengthwise Light Gray Part 3673 Element 4184166 or 367302 ×2

Tiles Special 6 pieces

  • Tile Special 1 x 1 with Clip and Straight Tips Black Part 2555 Element 255526 ×2
  • Tile Special 1 x 2 Grille with Bottom Groove Black Part 2412b Element 241226 ×2
  • Tile Special 1 x 2 Grille with Bottom Groove Yellow Part 2412b Element 241224 ×2

Bricks 4 pieces

  • Brick 1 x 3 Yellow Part 3622 Element 362224 ×2
  • Brick 1 x 4 Yellow Part 3010 Element 301024 ×2

Bricks Sloped 4 pieces

  • Brick Sloped 33° 3 x 2 Black Part 3298 Element 329826 ×4

Minifig Shields, Weapons, & Tools 4 pieces

  • Weapon Dagger / Knife Chrome Silver Part 37 Element 70749 ×2
  • Weapon Harpoon [4 Grooves on Shaft] Chrome Silver Part 57467 ×2

Transportation - Sea and Air 4 pieces

  • Propeller 3 Blade 3 Diameter with Axle Cross Trans-Neon Orange Part 6041 Element 4165521 or 604147 ×4

Minifig Accessories 2 pieces

  • Minifig Footwear Flipper [Thin] Blue Part 59275 ×2

Plates Special 2 pieces

  • Plate Special 1 x 2 with Bar Up [Horizontal Arm 6mm] Black Part 4623 Element 4597267 or 462326 ×2

Technic Axles 2 pieces

  • Technic Axle 10 Black Part 3737 Element 373726 ×2

Wheels and Tyres 2 pieces

  • Wheel Hard Plastic Medium (35mm D. x 31mm) Yellow Part 2593 Element 4106930 or 259324 ×2

Baseplates 1 piece

  • Baseplate Sea Floor Play Stage Blue Part 4101599 ×1

Plants & Trees 1 piece

  • Plant, Bush 2 x 2 x 4 Green Part 6064 Element 6269009 or 606428 ×1

Tiles 1 piece

  • Tile 1 x 2 with Underwater Navigation Print Yellow Part 3069bpr0093 Element 81819 ×1

Tiles Round and Curved 1 piece

  • Tile Round 2 x 2 with Black Background, Yellow Submarine Print Yellow Part 4150pr0029 Element 81824 ×1

Windscreens and Fuselage 1 piece

  • Windscreen 6 x 6 Octagonal Canopy with Axle hole Trans-Dark Blue Part 2418b Element 241843 ×1

Minifigures 1 figure

  • Aquanaut 2 Minifigure, checked as a whole figure ×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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