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.

Basic Building Set

Checking

520-16 Basic Building Set

169 pieces in 53 part and color combinations, plus 1 minifigure.

The piece count includes the 4 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.

Show

Piece checklist

Bricks 107 pieces

  • Brick 1 x 1 Blue Part 3005 Element 300523 ×8
  • Brick 1 x 2 Blue Part 3004 Element 4613959 or 300423 ×10
  • Brick 1 x 3 Blue Part 3622 Element 362223 ×4
  • Brick 1 x 4 Blue Part 3010 Element 301023 ×10
  • Brick 1 x 6 with Bottom Tubes and 2 Lowered Cross Supports Blue Part 3009b ×3
  • Brick 1 x 8 with Bottom Tubes and 3 Lowered Cross Supports Blue Part 3008b ×2
  • Brick 2 x 2 Blue Part 3003 Element 4103589 or 300373 ×3
  • Brick 2 x 3 Blue Part 3002 Element 300223 ×2
  • Brick 2 x 4 Blue Part 3001 Element 300173 or 300123 ×4
  • Brick 1 x 1 Red Part 3005 Element 300521 ×4
  • Brick 1 x 2 Red Part 3004 Element 4613961 or 300421 ×5
  • Brick 1 x 3 Red Part 3622 Element 362221 ×2
  • Brick 1 x 4 Red Part 3010 Element 301021 ×6
  • Brick 2 x 2 Red Part 3003 Element 4103590 or 300371 ×2
  • Brick 2 x 3 Red Part 3002 Element 300271 or 300221 ×2
  • Brick 2 x 4 Red Part 3001 Element 300121 ×3
  • Brick 1 x 1 Trans-Clear Part 3005 Element 6514207 or 6220959 ×2
  • Brick 1 x 2 Trans-Clear Part 3004 Element 4256587 or 300410 ×2
  • Brick 1 x 1 Yellow Part 3005 Element 300524 ×2
  • Brick 1 x 2 Yellow Part 3004 Element 4613966 or 300424 ×8
  • Brick 1 x 3 Yellow Part 3622 Element 362224 ×4
  • Brick 1 x 4 Yellow Part 3010 Element 301024 ×6
  • Brick 1 x 6 with Bottom Tubes and 2 Lowered Cross Supports Yellow Part 3009b ×3
  • Brick 2 x 2 Yellow Part 3003 Element 4103588 or 300374 ×4
  • Brick 2 x 3 Yellow Part 3002 Element 300224 ×2
  • Brick 2 x 4 Yellow Part 3001 Element 300124 ×4

Windows and Doors 16 pieces

  • Window 1 x 2 x 2 Classic, Short Lip [with Glass] Red Part 3081c01 Element 7026 ×2
  • Window 1 x 2 x 3 Pane Red Part 3854 Element 4175391 or 385421 ×6
  • Door 1 x 4 x 5 with 4 Panes, Squared Base White Part 3861b Element 4160992 or 386101 ×1
  • Window 1 x 2 x 3 Shutter White Part 3856 Element 4177767 or 385601 ×4
  • Window 1 x 4 x 3 White Part 3853 Element 4175392 or 385301 ×3

Bricks Sloped 15 pieces

  • Brick Sloped 33° 2 x 2 Double Red Part 3300 Element 330021 ×2
  • Brick Sloped 33° 2 x 4 Double Red Part 3299 Element 329921 ×1
  • Brick Sloped 33° 3 x 2 Red Part 3298 Element 329821 ×4
  • Brick Sloped 33° 3 x 4 Red Part 3297 Element 329721 ×2
  • Brick Sloped 45° 2 x 2 Red Part 3039 Element 303921 ×2
  • Brick Sloped Inverted 45° 2 x 2 [Ovoid Bottom Pin, Bar-sized Stud Holes] Red Part 3660 Element 366021 ×2
  • Brick Sloped 45° 2 x 2 Trans-Clear Part 3039 Element 6514100 or 6244886 ×2

Plates 13 pieces

  • Plate 1 x 4 Red Part 3710 Element 371021 ×2
  • Plate 2 x 2 Red Part 3022 Element 4613974 or 302221 ×2
  • Plate 2 x 3 Red Part 3021 Element 302121 ×2
  • Plate 2 x 4 Red Part 3020 Element 302021 ×2
  • Plate 2 x 8 Red Part 3034 Element 303421 ×2
  • Plate 4 x 4 Red Part 3031 Element 4243814 or 303121 ×2
  • Plate 4 x 6 Red Part 3032 Element 303221 ×1

Plants & Trees 8 pieces

  • Plant, Flower Stem Green Part 3741 Element 6277589 or 374128 ×2
  • Plant, Flower - Small Red Part 3742 1 spare in the box ×3
  • Plant, Flower - Small White Part 3742 1 spare in the box ×3

Wheels and Tyres 6 pieces

  • Brick Special 2 x 2 [Red Wheels for Single Tyre] Black Part 3137c01 ×2
  • Tyre 15 x 6 Offset Tread Small Black Part 3641 Element 4501046 or 364126 ×4

Bars, Ladders and Fences 2 pieces

  • Fence Lattice 1 x 4 x 1 Red Part 3633 Element 4187280 or 363321 ×2

Baseplates 1 piece

  • Baseplate 16 x 16 Green Part 3867 Element 4217115 or 609828 ×1

Windscreens and Fuselage 1 piece

  • Windscreen 2 x 4 x 2 Trans-Clear Part 3823 Element 6581801 or 6253681 ×1

Minifigures 1 figure

  • Blue Torso, White Legs, Red Hat 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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