Missing Piece Checker: 42075 First Responder

Checking

42075 First Responder

513 pieces in 107 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.

Every bag and the box. Shake out each bag, check its corners and seams, and look inside the empty box.
Inside what you have built. Small pieces lodge inside tubes, under plates and between studs. Turn the model over and look.
The last few steps. Compare each recent step with its parts callout. A piece used in the wrong place earlier leaves you one short later.
Look-alike colors. Compare each color with the step's parts callout, especially White against Trans-Clear.
The spare pieces. This set comes with 13 spare pieces, marked on each row of the checklist. One may be the piece you need.
The floor and your building area. Check under furniture, the chair and the edges of your building surface.

Piece checklist

Technic Pins 177 pieces

Technic Axle Pin 3L with Friction Ridges Lengthwise and 2L Axle Black Part 18651 Element 6089119 ×2
Technic Pin with Friction Ridges Lengthwise and Center Slots Black Part 2780 Element 4121715 or 278026 2 spares in the box ×77
Technic Axle Pin with Friction Ridges Lengthwise Blue Part 43093 Element 4309323 or 4206482 ×9
Technic Pin 1/2 without Friction Ridges Blue Part 4274 Element 4143005 1 spare in the box ×15
Technic Pin Long with Friction Ridges Lengthwise, 2 Center Slots Blue Part 6558 Element 4514553 ×40
Technic Pin 1/2 without Friction Ridges Light Bluish Gray Part 4274 Element 4274194 or 4211483 1 spare in the box ×10
Technic Pin Long with Friction Ridges Lengthwise and Stop Bush [3 Lateral Holes, Big Pin Hole] Light Bluish Gray Part 32054 Element 4211865 ×7
Technic Axle Pin 3L with Friction Ridges Lengthwise and 1L Axle Red Part 11214 Element 6209519 ×15
Technic Pin Long without Friction Ridges Tan Part 32556 ×2

Technic Gears 18 pieces

Technic Gear 12 Tooth Double Bevel Black Part 32270 Element 4177431 ×6
Technic Gear Rack 1 x 7 with Axle and Pin Holes Black Part 87761 Element 6327430 or 4562009 ×1
Technic Gear Differential with Inner Tabs and Closed Center, 28 Bevel Teeth [Beveled Edge] Dark Bluish Gray Part 62821b Element 4562210 or 4525184 ×1
Technic Gear 16 Tooth Reinforced [New Style] Light Bluish Gray Part 94925 Element 4640536 ×2
Technic Gear 16 Tooth with Clutch on Both Sides Red Part 18946 Element 6100930 ×1
Technic Gear 12 Tooth Bevel Tan Part 6589 Element 4565452 or 4514556 ×4
Technic Gear 20 Tooth Double Bevel with Axle Hole Type 1 [+ Opening] Tan Part 18575 Element 6346517 or 6084724 ×3

Technic Bushes 17 pieces

Technic Bush Red Part 3713 Element 6271820 or 4227155 1 spare in the box ×17

Tiles Round and Curved 16 pieces

Tile Round 1 x 1 Trans-Clear Part 98138 Element 6514191 or 6274738 1 spare in the box ×4
Tile Round 1 x 1 Trans-Dark Blue Part 98138 Element 6514190 or 6273627 1 spare in the box ×4
Tile Round 1 x 1 Trans-Orange Part 98138 Element 6514197 or 6274747 1 spare in the box ×6
Tile Round 1 x 1 Trans-Red Part 98138 Element 6514189 or 6258607 1 spare in the box ×2

Technic Panels 12 pieces

Technic Panel Curved and Bent 6 x 3 Blue Part 24116 Element 6268009 or 6133684 ×2
Technic Panel 3 x 11 x 1 Dark Bluish Gray Part 15458 Element 6127205 ×2
Technic Panel Curved 11 x 3 with 10 Pin Holes through Panel Surface Red Part 11954 Element 6036771 ×2
Technic Panel Fairing # 3 Small Smooth Long, Side A Red Part 64683 Element 4540801 ×2
Technic Panel Fairing # 4 Small Smooth Long, Side B Red Part 64391 Element 4540798 ×2
Technic Panel Fairing #21 5L Small Smooth, Side B Red Part 11946 Element 6340601 or 6022750 ×1
Technic Panel Fairing #22 5L Small Smooth, Side A Red Part 11947 Element 6343986 or 6022752 ×1

Technic Steering, Suspension and Engine 11 pieces

Technic Engine Connecting Rod Light Bluish Gray Part 2852 Element 6000018 or 4655728 ×2
Technic Engine Cylinder without Side Slots, with Bottom Slots Light Bluish Gray Part 2850b Element 6514436 or 6383961 ×2
Technic Steering Wheel Small (3 Studs Diameter) Light Bluish Gray Part 2819 Element 4580510 or 4211578 ×1
Technic Universal Joint 3L [Complete Assembly] Light Bluish Gray Part 61903 Element 6335279 or 6321309 ×1
Technic Engine Crankshaft Yellow Part 2853 Element 6640378 or 4119474 ×2
Technic Engine Piston Round Yellow Part 2851 Element 4112203 or 285124 ×2
Technic Shock Absorber 6.5L with Hard Spring, Tight Coil in Middle [Complete Assembly] Yellow Part 76537 Element 7653726 or 6027566 ×1

Wheels and Tyres 8 pieces

Tyre 49.53 x 20 Black Part 15413 Element 6518565 or 6055626 ×4
Wheel 30.4 x 20 without Pinholes, with Reinforced Rim Black Part 56145 Element 4299389 or 4284946 ×4

Plates Round Curved and Dishes 6 pieces

Plate Round 2 x 2 with Axle Hole Type 1 (+ Opening) Black Part 4032a Element 403226 ×1
Plate Round 2 x 2 with Rounded Bottom [Boat Stud] Trans-Clear Part 2654 Element 6581772 or 6163901 ×1
Plate Round 1 x 1 with Solid Stud White Part 6141 Element 6601919 or 614101 1 spare in the box ×4

Technic Beams Special 5 pieces

Technic Beam Frame 5 x 7 with 3 x 5 Opening Thick Black Part 64179 Element 6016154 ×1
Technic Beam 3 x 5 Thick [90° Offset Centre Beam Holes] Light Bluish Gray Part 14720 Element 6055519 ×2
Technic Beam 5 x 11 with 3 x 5 Opening Frame Thick Light Bluish Gray Part 64178 Element 4540797 ×2

Bricks Round and Cones 4 pieces

Cone 2 x 2 x 2, Open Stud Orange Part 3942c Element 6533789 or 6062601 ×2
Brick Round 1 x 1 diameter Tube with 90 Degree Elbow (2 x 2 x 1) and Axle Holes (Crossholes) at each end Red Part 25214 Element 6176298 ×2

Bricks Sloped 4 pieces

Brick Sloped 30° 1 x 1 x 2/3 (Cheese Slope) Trans-Dark Blue Part 54200 Element 6245256 or 4244366 1 spare in the box ×4

Plates 4 pieces

Plate 1 x 2 Trans-Dark Blue Part 3023 Element 6514004 or 6240215 ×2
Plate 1 x 4 White Part 3710 Element 6552108 or 6548266 ×2

String, Bands and Reels 2 pieces

String Cord Thin (0.5mm) 50cm Black Part 56823c50 Element 6530026 or 6489925 ×1
String Reel 2 x 1 x 2 Drum with Axle Hole Light Bluish Gray Part 61510 Element 4521532 ×1

Tiles 2 pieces

Tile 1 x 2 with Groove Trans-Dark Blue Part 3069b Element 6514219 or 6251289 ×2

Minifig Accessories 1 piece

Tap 1 x 1 without Hole in Spout Light Bluish Gray Part 4599b Element 4211503 1 spare in the box ×1

Minifig Shields, Weapons, & Tools 1 piece

Weapon Axe Black Part 3835 Element 383526 ×1

Stickers 1 piece

Sticker Sheet for Set 42075-1 [No Color/Any Color] Part 37609 Element 6219399 ×1

Supports, Girders and Cranes 1 piece

Hook with Towball Dark Bluish Gray Part 30395 Element 30395199 or 6347464 ×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.

LEGO Missing Piece Checker

42075 First Responder

Before you call it missing

Your missing list