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Robotics Invention System, Version 2.0

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3804 Robotics Invention System, Version 2.0

720 pieces in 144 part and color combinations.

LEGO counts 717 pieces. This inventory comes from a separate parts catalog and lists 720; 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.

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Piece checklist

Plates 103 pieces

  • Plate 2 x 2 Blue Part 3022 Element 4613973 or 302223 ×4
  • Plate 2 x 2 Green Part 3022 Element 302228 ×2
  • Plate 2 x 8 Green Part 3034 Element 303428 ×4
  • Plate 1 x 1 Light Gray Part 3024 Element 302402 ×8
  • Plate 1 x 10 Light Gray Part 4477 Element 447702 ×6
  • Plate 1 x 2 Light Gray Part 3023 Element 302302 ×20
  • Plate 1 x 4 Light Gray Part 3710 Element 371002 ×10
  • Plate 1 x 6 Light Gray Part 3666 Element 366602 ×10
  • Plate 1 x 8 Light Gray Part 3460 Element 346002 ×8
  • Plate 2 x 10 Light Gray Part 3832 Element 383202 ×6
  • Plate 2 x 2 Light Gray Part 3022 Element 302202 ×8
  • Plate 2 x 2 Corner Light Gray Part 2420 Element 242052 or 242002 ×8
  • Plate 6 x 10 Light Gray Part 3033 Element 303302 ×1
  • Plate 1 x 3 Yellow Part 3623 Element 362324 ×2
  • Plate 2 x 4 Yellow Part 3020 Element 302024 ×6

Technic Pins 102 pieces

  • Technic Pin Long with Friction Ridges Lengthwise, 2 Center Slots Black Part 6558 Element 655826 ×8
  • Technic Pin with Friction Ridges Lengthwise and Center Slots Black Part 2780 Element 4121715 or 278026 1 spare in the box ×24
  • Technic Pin Long with Friction Ridges Lengthwise and Stop Bush [3 Lateral Holes, Big Pin Hole] Blue Part 32054 Element 4140800 or 4107741 ×4
  • Technic Pin 3/4 Dark Gray Part 32002 Element 4109854 1 spare in the box ×16
  • Technic Axle Pin without Friction Ridges Lengthwise Light Gray Part 3749 Element 4184168 or 4154179 ×16
  • Technic Pin 1/2 without Friction Ridges Light Gray Part 4274 Element 427402 1 spare in the box ×8
  • Technic Pin without Friction Ridges Lengthwise Light Gray Part 3673 Element 4184166 or 367302 ×24
  • Technic Pin Double with Axle Hole Yellow Part 32138 Element 4130596 or 4119438 ×2

Technic Bricks 68 pieces

  • Technic Brick 1 x 10 [9 Pin Holes] Black Part 2730 Element 273026 ×8
  • Technic Brick 1 x 12 [11 Pin Holes] Black Part 3895 Element 389526 ×6
  • Technic Brick 1 x 16 [15 Pin Holes] Black Part 3703 Element 370326 ×6
  • Technic Brick 1 x 2 [1 Pin Hole] Black Part 3700 Element 370026 ×12
  • Technic Brick 1 x 4 [3 Pin Holes] Black Part 3701 Element 370126 ×10
  • Technic Brick 1 x 6 [5 Pin Holes] Black Part 3894 Element 389426 ×8
  • Technic Brick 1 x 8 [7 Pin Holes] Black Part 3702 Element 370226 ×8
  • Technic Brick 1 x 2 with Axle Hole Type 1 [+ Opening] and Bottom Ridges Green Part 32064c ×4
  • Technic Brick 1 x 4 [3 Pin Holes] Green Part 3701 Element 4107790 ×2
  • Technic Brick 1 x 2 [1 Pin Hole] Yellow Part 3700 Element 370024 ×4

Technic Bushes 58 pieces

  • Technic Bush Light Gray Part 3713 Element 4125313 or 659002 1 spare in the box ×40
  • Technic Bush 1/2 Smooth with Axle Hole Reduced Light Gray Part 32123a 1 spare in the box ×18

Bricks 49 pieces

  • Brick 1 x 2 Black Part 3004 Element 300426 ×20
  • Brick 2 x 2 Black Part 3003 Element 4103587 or 300326 ×20
  • Brick 2 x 4 Black Part 3001 Element 300126 ×5
  • Brick 1 x 2 Yellow Part 3004 Element 4613966 or 300424 ×4

Technic Axles 45 pieces

  • Technic Axle 10 Black Part 3737 Element 373726 ×4
  • Technic Axle 12 Black Part 3708 Element 370826 ×2
  • Technic Axle 2 Notched Black Part 32062 Element 4109810 or 3206226 ×10
  • Technic Axle 3 Black Part 4519 Element 6238084 or 451926 ×3
  • Technic Axle 4 Black Part 3705 Element 370526 ×7
  • Technic Axle 5 Black Part 32073 Element 4114740 ×2
  • Technic Axle 6 Black Part 3706 Element 370626 ×8
  • Technic Axle 8 Black Part 3707 Element 370726 ×7
  • Technic Axle 3 with Stud Dark Gray Part 6587 Element 4113884 or 658727 ×2

Wheels and Tyres 42 pieces

  • Technic Wedge Belt Wheel Tire Black Part 2815 Element 6028041 or 281526 ×2
  • Tread Large, Technic [34 Links] Black Part 71372 Element 4107488 ×2
  • Tyre 30 x 10.5 Offset Tread Black Part 2346 Element 234676 or 234626 ×4
  • Tyre 30.4 x 14 VR Black Part 6578 Element 4561806 or 657826 ×2
  • Tyre 43 x 17 Black Part 3634 Element 4523564 or 363426 ×2
  • Tyre 49.6 x 28 VR Black Part 6594 Element 75778 ×2
  • Tyre 81.6 x 15 Motorcycle Black Part 2902 Element 6226880 or 4562873 ×4
  • Tyre Offset Tread 24 x 8 Black Part 3483 Element 4501048 or 348326 ×2
  • Technic Wedge Belt Wheel [aka Pulley] Light Gray Part 4185 Element 4100502 or 418502 ×4
  • Technic Tread Hub White Part 32007 Element 4107487 ×4
  • Wheel 49.6 x 28 VR (36.8 x 26) with Axle Hole White Part 6595 Element 4496709 or 4179486 ×2
  • Wheel 61.6 x 13.6 Motorcycle White Part 2903 Element 290301 ×4
  • Wheel Rim 24 x 14 VR with Center Axle Hole White Part 2994 Element 4496671 or 299401 ×2
  • Wheel with Split Axle hole Yellow Part 3482 Element 348224 ×6

Technic Gears 35 pieces

  • Technic Worm Gear Black Part 4716 Element 6037533 or 471626 ×2
  • Technic Gear Differential, 24 -16 Tooth with Clutch on Both Sides Dark Gray Part 6573 Element 657327 ×1
  • Technic Gear 12 Tooth Bevel Light Gray Part 6589 Element 658902 ×5
  • Technic Gear 16 Tooth with Round Holes [Old Style] Light Gray Part 4019 Element 4107176 or 401902 ×4
  • Technic Gear 24 Tooth Crown with Reinforcements [New Style] Light Gray Part 3650c Element 365002 ×4
  • Technic Gear 24 Tooth [New Style with Single Axle Hole] Light Gray Part 3648b Element 4107543 or 364802 ×4
  • Technic Gear 40 Tooth Light Gray Part 3649 Element 364902 ×4
  • Technic Gear 8 Tooth Light Gray Part 3647 Element 364702 1 spare in the box ×6
  • Technic Gear Rack 1 x 4 Light Gray Part 3743 Element 374302 ×4
  • Technic Gear 24 Tooth Clutch with Dark Gray or Light Gray Center White Part 76019 Element 4270486 ×1

Plates Special 34 pieces

  • Plate Special 1 x 1 with Clip Horizontal [Thick U Clip] Black Part 6019 Element 601976 or 601926 ×2
  • Plate Special 1 x 1 with Clip Vertical [Thick U Clip] Black Part 4085c Element 408526 ×2
  • Bracket 2 x 2 - 2 x 2 Light Gray Part 3956 Element 395602 ×2
  • Plate Special 1 x 2 with Door Rail Light Gray Part 32028 Element 4109642 ×8
  • Plate Special 2 x 2 with 2 Pin Holes Light Gray Part 2817 Element 281702 ×4
  • Technic Plate 2 x 4 [3 Holes] Light Gray Part 3709 Element 370902 ×4
  • Technic Plate 2 x 6 [5 Holes] Light Gray Part 32001 Element 3200102 ×4
  • Technic Plate 2 x 8 [7 Holes] Light Gray Part 3738 Element 373802 ×8

Technic Connectors 30 pieces

  • Technic Axle and Pin Connector Angled #1 Blue Part 32013 Element 6332570 or 4107797 ×4
  • Technic Axle and Pin Connector Angled #2 - 180° Blue Part 32034 Element 6484676 or 4107798 ×2
  • Technic Axle 1.5 with Perpendicular Axle Connector (Technic Pole Reverser Handle) Light Gray Part 6553 Element 655302 ×2
  • Technic Axle Connector Ridged [with x Hole x Orientation] Light Gray Part 6538b Element 4113804 or 4100408 ×4
  • Technic Axle Connector with Axle Hole Light Gray Part 32039 Element 4106469 ×2
  • Technic Axle and Pin Connector Angled #5 - 112.5° Light Gray Part 32015 Element 4106378 ×4
  • Technic Axle and Pin Connector Perpendicular Light Gray Part 6536 Element 4173667 or 653602 ×6
  • Technic Axle and Pin Connector Perpendicular 3L with Pin Hole Light Gray Part 32068 Element 4114669 ×2
  • Technic Modular Connector Trans-Dark Blue Part 32137 Element 4118978 ×4

Bricks Sloped 28 pieces

  • Brick Sloped 45° 2 x 1 with Bottom Pin Black Part 3040b Element 4121966 or 304026 ×12
  • Brick Sloped Inverted 33° 3 x 2, No Connections between Studs, Ovoid Bottom Pin Black Part 3747a ×4
  • Brick Sloped Inverted 45° 2 x 1 Black Part 3665 Element 366526 ×4
  • Brick Sloped 45° 2 x 1 with Bottom Pin Yellow Part 3040b Element 4121965 or 304024 ×4
  • Brick Sloped Inverted 45° 2 x 1 Yellow Part 3665 Element 366524 ×4

Technic Beams 28 pieces

  • Technic Beam 1 x 7 Thin Black Part 32065 Element 6271573 or 6253293 ×4
  • Technic Beam 1 x 9 Bent (6 - 4) Thick Black Part 6629 Element 6279881 or 4119800 ×4
  • Technic Beam 2 x 4 L-Shape Thick Black Part 32140 Element 6271825 or 4120017 ×2
  • Technic Beam 1 x 3 Thin Light Gray Part 6632 Element 4107825 ×4
  • Technic Beam 1 x 4 Thin with Stud Connector Light Gray Part 2825 Element 4107133 or 282502 ×2
  • Technic Beam 1 x 5 Thin Light Gray Part 32017 Element 4106885 ×4
  • Technic Beam 3 x 3 L-Shape Thin Light Gray Part 32056 Element 4111941 ×4
  • Technic Beam 1 x 11.5 Double Bent Thick Yellow Part 32009 Element 6271150 or 6257104 ×4

Electronics 16 pieces

  • Wire with Brick 2 x 2 x 2/3 Pair, 162L Black Part 5306bc162 Element 75656 ×2
  • Wire with Brick 2 x 2 x 2/3 Pair, 20L Black Part 5306bc020 Element 4100355 ×4
  • Sensor, Light with Fixed Cable Blue Part 2982c01 Element 4119421 ×1
  • Transmitter Tower, IR, USB Cable, with Black Front Dark Gray Part 23319c01 ×1
  • Motor Pulley, 9V Micromotor with axle hole Light Gray Part 2983 Element 298630 ×2
  • Motor, 9V Mini [Old Style] Light Gray Part 71427c01 Element 4107786 ×2
  • Sensor, Touch Light Gray Part 879 Element 4247135 or 4209116 ×2
  • Cable, Fiber Optics, Wide 25L / 20.0cm Trans-Clear Part 40002c25 ×1
  • Hub, RCX 2.0, No Power Jack [Complete Assembly] Yellow Part 884c ×1

Hinges, Arms and Turntables 16 pieces

  • Arm Grab Jaw Black Part 4221 Element 422126 ×4
  • Arm Piece with Pin, 2 Fingers Black Part 6048a Element 604826 ×2
  • Hinge Plate 1 x 2 with 3 Fingers [Hollow Studs] Black Part 4275b Element 427526 ×2
  • Hinge Tile 1 x 2 1/2 with 2 Fingers on Top Black Part 4531 Element 453126 ×2
  • Turntable 2 x 2 Plate, Base Blue Part 3680 Element 368023 ×2
  • Turntable 2 x 2 Plate - Top Light Gray Part 3679 Element 367952 or 367902 ×2
  • Arm Grab Jaw Holder, 3 Fingers Yellow Part 4220 Element 4107528 or 422024 ×2

Plates Round Curved and Dishes 14 pieces

  • Plate Round 1 x 1 with Solid Stud Black Part 6141 Element 614126 1 spare in the box ×2
  • Plate Round 2 x 2 with Rounded Bottom [Boat Stud] Black Part 2654 Element 4617551 or 4278359 ×2
  • Plate Round 1 x 1 with Solid Stud Blue Part 6141 Element 614123 1 spare in the box ×2
  • Plate Round 2 x 2 with Axle Hole Type 1 (+ Opening) Blue Part 4032a Element 403223 ×2
  • Dish 4 x 4 Inverted [Radar] White Part 3960 Element 396001 ×2
  • Plate Round 1 x 1 with Solid Stud White Part 6141 Element 6601919 or 614101 1 spare in the box ×2
  • Plate Round 2 x 2 with Axle Hole Type 1 (+ Opening) White Part 4032a Element 6601914 or 403201 ×2

Tubes and Hoses 14 pieces

  • Hose, Ribbed 7mm D. 9L / 7.2cm Black Part 78c09 Element 6443871 or 6420612 ×4
  • Hose, Ribbed 7mm D. 9L / 7.2cm Dark Turquoise Part 78c09 Element 4275293 or 4114737 ×4
  • Hose, Ribbed 7mm D. 12L / 9.6cm Purple Part 78c12 Element 4275294 or 4114738 ×4
  • Hose Rigid 3mm D. 19L / 15.2cm Yellow Part 75c19 Element 4579744 or 4118600 ×2

String, Bands and Reels 13 pieces

  • Rubber Band Small 13mm (Square Cross Section) Black Part 71509 Element 4141606 or 4107153 1 spare in the box ×4
  • Technic Rubber Belt Medium [26mm ID] [Round Cross Section] Blue Part 85545 Element 6049730 or 4544147 ×3
  • Rubber Belt Small [15mm ID] [Round Cross Section] White Part 85543 Element 6699001 or 4580665 1 spare in the box ×3
  • Technic Rubber Belt Large [33mm ID] [Round Cross Section] Yellow Part 85546 Element 4544151 or 70905 ×3

Bricks Round and Cones 12 pieces

  • Brick Round 2 x 2 with Axle Hole Black Part 3941 Element 614376 or 614326 ×8
  • Cone 1 x 1 [No Top Groove] White Part 4589 Element 458901 ×2
  • Cone 1 x 1 [No Top Groove] Yellow Part 4589 Element 458924 ×2

Technic Steering, Suspension and Engine 4 pieces

  • Technic Engine Crankshaft Center Light Gray Part 2854 Element 285402 ×2
  • Technic Steering Pulley Large Light Gray Part 3736 Element 373602 ×2

Animal / Creature Body Parts 2 pieces

  • Creature Body Part, Dragon Wing Trans-Neon Orange Part 6133 Element 4106519 ×2

Plates Wedged 2 pieces

  • Wedge Plate 3 x 6 Cut Corners Green Part 2419 Element 241928 ×2

Technic Special 2 pieces

  • Technic Cam Light Gray Part 6575 Element 657502 ×2

Gear Parts 1 piece

  • CD-Rom, for 3804 [RIS v2.0] [No Color/Any Color] Part 4142876 ×1

Non-System Parts 1 piece

  • Playmat, Test Mat for Mindstorms Robotics Invention System [v2.0] [No Color/Any Color] Part 4153678 ×1

Tools 1 piece

  • Brick Separator v1.0 Dark Gray Part 6007 Element 600727 ×1

Tick each piece as you find it, or mark it missing.

When a piece really is missing

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