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Monorail Transport Base

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6991 Monorail Transport Base

551 pieces in 174 part and color combinations, plus 4 minifigures.

The piece count includes the 22 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

Plates 152 pieces

  • Plate 1 x 1 Black Part 3024 Element 302426 ×2
  • Plate 1 x 10 Black Part 4477 Element 447726 ×3
  • Plate 1 x 2 Black Part 3023 Element 302326 ×18
  • Plate 1 x 3 Black Part 3623 Element 362326 ×6
  • Plate 1 x 4 Black Part 3710 Element 371026 ×38
  • Plate 1 x 6 Black Part 3666 Element 366626 ×4
  • Plate 1 x 8 Black Part 3460 Element 346026 ×4
  • Plate 2 x 16 Black Part 4282 Element 428276 or 428226 ×2
  • Plate 2 x 2 Black Part 3022 Element 302226 ×10
  • Plate 2 x 2 Corner Black Part 2420 Element 242026 ×2
  • Plate 2 x 4 Black Part 3020 Element 302026 ×3
  • Plate 2 x 6 Black Part 3795 Element 379526 ×2
  • Plate 2 x 8 Black Part 3034 Element 303426 ×2
  • Plate 4 x 10 Black Part 3030 Element 303076 or 303026 ×1
  • Plate 4 x 6 Black Part 3032 Element 303226 ×1
  • Plate 4 x 8 Black Part 3035 Element 303526 ×3
  • Plate 6 x 16 Black Part 3027 Element 302726 ×1
  • Plate 1 x 2 Blue Part 3023 Element 302323 ×20
  • Plate 1 x 3 Blue Part 3623 Element 362323 ×4
  • Plate 1 x 8 Blue Part 3460 Element 346023 ×4
  • Plate 2 x 2 Blue Part 3022 Element 4613973 or 302223 ×2
  • Plate 1 x 2 Light Gray Part 3023 Element 302302 ×8
  • Plate 1 x 4 Light Gray Part 3710 Element 371002 ×3
  • Plate 2 x 10 Light Gray Part 3832 Element 383202 ×1
  • Plate 2 x 12 Light Gray Part 2445 Element 244502 ×2
  • Plate 2 x 2 Light Gray Part 3022 Element 302202 ×4
  • Plate 2 x 4 Light Gray Part 3020 Element 302002 ×1
  • Plate 4 x 6 Light Gray Part 3032 Element 303202 ×1

Bricks 53 pieces

  • Brick 1 x 1 x 5 with Blocked Open or Hollow Stud Black Part 2453a Element 245326 ×2
  • Brick 1 x 10 Black Part 6111 Element 611126 ×2
  • Brick 1 x 16 Black Part 2465 Element 246576 or 246526 ×3
  • Brick 1 x 2 Black Part 3004 Element 300426 ×3
  • Brick 1 x 6 Black Part 3009 Element 300926 ×2
  • Brick 1 x 8 Black Part 3008 Element 300826 ×3
  • Brick 2 x 2 Black Part 3003 Element 4103587 or 300326 ×2
  • Brick 2 x 3 Black Part 3002 Element 300226 ×2
  • Brick 2 x 4 Black Part 3001 Element 300126 ×1
  • Brick 1 x 10 Light Gray Part 6111 Element 611102 ×2
  • Brick 1 x 16 Light Gray Part 2465 Element 246502 ×6
  • Brick 1 x 2 Light Gray Part 3004 Element 300402 ×10
  • Brick 1 x 4 Light Gray Part 3010 Element 301002 ×2
  • Brick 1 x 8 Light Gray Part 3008 Element 300802 ×4
  • Brick 2 x 2 Light Gray Part 3003 Element 4103591 or 300352 ×2
  • Brick 2 x 2 Corner Light Gray Part 2357 Element 235752 or 235702 ×2
  • Brick 2 x 3 Light Gray Part 3002 Element 300252 or 300202 ×2
  • Brick 2 x 4 Light Gray Part 3001 Element 4116259 or 300102 ×2
  • Brick 2 x 8 Light Gray Part 3007 Element 300702 ×1

Plates Special 45 pieces

  • Bracket 1 x 2 - 1 x 4 [Square Corners] Black Part 2436 Element 4282746 or 243626 ×1
  • Bracket 2 x 2 - 2 x 2 Black Part 3956 Element 6254808 or 6019217 ×2
  • Plate Special 1 x 1 with Clip Horizontal [Thick U Clip] Black Part 6019 Element 601976 or 601926 ×3
  • Plate Special 1 x 1 with Clip Light, Bar Hole [Thick Ring] Black Part 4081b Element 6281993 or 4632571 ×2
  • Plate Special 1 x 1 with Clip Vertical [Thick U Clip] Black Part 4085c Element 408526 ×1
  • Plate Special 1 x 2 with 1 Stud without Groove (Jumper) Black Part 3794a ×1
  • Plate Special 1 x 2 with Handles [Flat Ends / Low Attachment] Black Part 3839b Element 383926 ×1
  • Plate Special 1 x 4 Offset with Bar Holes Black Part 4590 Element 6002559 or 4278029 ×3
  • Plate Special 2 x 2 with 1 Pin Hole [Split Underside Ribs] Black Part 2444 Element 244426 ×5
  • Plate Special 8 x 8 with Grille [No Hole in Center] Black Part 4151a ×4
  • Technic Plate 2 x 8 [7 Holes] Black Part 3738 Element 373826 ×2
  • Plate Special 1 x 1 with Clip Horizontal [Thick U Clip] Blue Part 6019 Element 601973 or 601923 ×4
  • Plate Special 1 x 2 with Handles [Flat Ends / Low Attachment] Blue Part 3839b Element 4286615 or 383923 ×1
  • Plate Special 1 x 1 with Clip Light, Bar Hole [Thick Ring] Light Gray Part 4081b Element 408102 ×2
  • Plate Special 1 x 2 Side Handle [Free Ends] Light Gray Part 2540 Element 4140584 or 254052 ×2
  • Plate Special 1 x 2 with 1 Stud without Groove (Jumper) Light Gray Part 3794a Element 379402 ×6
  • Plate Special 1 x 2 with Long Stud Receptacle (Space Wing) Light Gray Part 4596 Element 4188363 or 459602 ×2
  • Plate Special 2 x 2 with 1 Pin Hole [Split Underside Ribs] Light Gray Part 2444 Element 244402 ×2
  • Plate Special 3 x 2 with Rounded End, Hole Light Gray Part 3176 Element 317652 or 317602 ×1

Supports, Girders and Cranes 35 pieces

  • Support 4 x 4 x 5 Stanchion, Tall Studs Black Part 2680 Element 268026 ×2
  • Support 6 x 6 x 10 Stanchion Black Part 2681 Element 268126 ×23
  • Support Round 2 x 2 x 2 Stand with Reach-Through Center Hole Black Part 3940b Element 394026 ×4
  • Support 2 x 4 x 5 Stanchion Inclined [5mm wide posts] Light Gray Part 4476b Element 4142126 or 447602 ×6

Plates Round Curved and Dishes 33 pieces

  • Dish 6 x 6 Inverted, Radar / Webbed [No Anti-studs] Black Part 4285a ×1
  • Plate Round 2 x 2 with Axle Hole Type 1 (+ Opening) Blue Part 4032a Element 403223 ×2
  • Plate Round 2 x 2 with Axle Hole Type 1 (+ Opening) Light Gray Part 4032a Element 403202 ×7
  • Plate Round 2 x 2 with Rounded Bottom [Boat Stud] Light Gray Part 2654 Element 265402 ×3
  • Dish 2 x 2 Inverted [Radar] Trans-Dark Blue Part 4740 Element 6580383 or 6398233 ×3
  • Dish 4 x 4 Inverted [Radar] Trans-Dark Blue Part 3960 Element 4218661 or 3006543 ×4
  • Dish 2 x 2 Inverted [Radar] Trans-Neon Green Part 4740 Element 6245297 or 4112517 ×5
  • Plate Round 1 x 1 with Solid Stud Trans-Neon Green Part 6141 Element 6240223 or 3005749 ×8

Bricks Sloped 31 pieces

  • Brick Sloped 33° 3 x 2 Black Part 3298 Element 329826 ×2
  • Brick Sloped 45° 2 x 1 with Bottom Pin Black Part 3040b Element 4121966 or 304026 ×2
  • Brick Sloped 45° 2 x 2 Black Part 3039 Element 303926 ×5
  • Brick Sloped 45° 2 x 2 with Horizon Screen Print Black Part 3039pr9973 Element 4240154 or 82056 ×4
  • Brick Sloped 45° 2 x 2 with Spyrius Droid Image Print Black Part 3039pr9968 ×1
  • Brick Sloped Inverted 33° 3 x 2, No Connections between Studs, Ovoid Bottom Pin Black Part 3747a ×1
  • Brick Sloped 33° 2 x 2 Double Blue Part 3300 Element 330023 ×3
  • Brick Sloped 33° 3 x 1 Light Gray Part 4286 Element 428602 ×1
  • Brick Sloped 33° 3 x 2 Light Gray Part 3298 Element 329802 ×3
  • Brick Sloped 33° 3 x 4 Light Gray Part 3297 Element 329702 ×2
  • Brick Sloped 45° 2 x 1 with Bottom Pin Light Gray Part 3040b Element 4121933 or 304002 ×4
  • Brick Sloped 45° 2 x 2 Light Gray Part 3039 Element 303902 ×2
  • Brick Sloped Inverted 45° 2 x 2 [Ovoid Bottom Pin, Bar-sized Stud Holes] Light Gray Part 3660 Element 366002 ×1

Tiles 31 pieces

  • Tile 1 x 2 with Arrow Long Yellow with Black Border Print Black Part 3069bpr9981 Element 81067 ×3
  • Tile 1 x 2 with Arrow Short Yellow without Black Border Print Black Part 3069bpr0038 Element 82057 ×2
  • Tile 1 x 4 with Groove Black Part 2431 Element 243126 ×2
  • Tile 1 x 8 with Groove Black Part 4162 Element 416226 ×4
  • Tile 2 x 2 with Groove Black Part 3068b Element 306826 ×3
  • Tile 2 x 2 with Yellow Arrow without Border Print Black Part 3068bpr0021 Element 81152 ×2
  • Tile 1 x 8 with Groove Blue Part 4162 Element 416223 ×4
  • Tile 1 x 4 with Groove Light Gray Part 2431 Element 243102 ×4
  • Tile 1 x 8 with Groove Light Gray Part 4162 Element 416202 ×6
  • Tile 1 x 2 with Digital Clock Print - '12:01' or '10:21' White Part 3069bpr0025 Element 81268 ×1

Transportation - Land 25 pieces

  • Vehicle Base, Monorail 4 x 20 Black Part 2687 ×2
  • Wheel Holder, Monorail Bogey with Bogey Bracket/Pivot Black Part 2686c01 ×2
  • Steering Stand 1 x 2 with Black Steering Wheel Light Gray Part 3829c01 Element 9556 ×1
  • Vehicle Track, Monorail Curve Long Light Gray Part 2672 ×4
  • Vehicle Track, Monorail Curve Short Left Light Gray Part 2892 ×1
  • Vehicle Track, Monorail Curve Short Right Light Gray Part 2891 ×1
  • Vehicle Track, Monorail Monoswitch Light Gray Part 2774 ×2
  • Vehicle Track, Monorail Point Left Light Gray Part 2886c01 ×1
  • Vehicle Track, Monorail Point Right Light Gray Part 2881c01 ×1
  • Vehicle Track, Monorail Ramp Lower Part Light Gray Part 2677 ×2
  • Vehicle Track, Monorail Straight Short Light Gray Part 2670 ×5
  • Vehicle Track, Monorail Track Ramp Upper Part Light Gray Part 2678 ×2
  • Vehicle Track, Monorail Track Straight Long Light Gray Part 2671 ×1

Tiles Special 24 pieces

  • Tile Special 1 x 1 with Clip and Straight Tips Black Part 2555 Element 255526 ×1
  • Tile Special 1 x 2 Grille with Bottom Groove Black Part 2412b Element 241226 ×6
  • Tile Special 1 x 2 Grille with Bottom Groove Blue Part 2412b Element 241223 ×1
  • Tile Special 1 x 2 Grille with Bottom Groove Light Gray Part 2412b Element 241202 ×16

Transportation - Sea and Air 17 pieces

  • Brick Special 1 x 1 with 3 Speakers / Loudspeakers / Space Positioning Rockets Black Part 3963 Element 4200791 or 396326 ×2
  • Engine, Strakes, 2 x 2 Thin Top Plate Black Part 4229 Element 4552040 or 4163480 ×1
  • Brick Special 1 x 1 with 3 Speakers / Loudspeakers / Space Positioning Rockets Blue Part 3963 Element 396323 ×2
  • Engine - Smooth, Small 1 x 2 Side Plate [With Axle Holders] Blue Part 3475b Element 347523 ×6
  • Tail 4 x 2 x 2 Light Gray Part 3479 Element 347952 or 347902 ×2
  • Wing, Tail 4 x 1 x 3 Light Gray Part 2340 Element 234002 ×4

Panels 13 pieces

  • Panel 1 x 2 x 3 - Solid Studs Black Part 2362a Element 4113027 ×4
  • Panel 10 x 6 x 11 Trans-Dark Blue Part 2408 Element 240843 ×2
  • Panel 3 x 2 x 6 Trans-Dark Blue Part 2466 Element 4109865 or 246643 ×7

Hinges, Arms and Turntables 12 pieces

  • Hinge Bar 2.5L with 2 and 3 Fingers on Ends (Pantograph Shoe Holder) Black Part 2923 Element 292326 ×2
  • Hinge Plate 1 x 2 with 2 Fingers and Hollow Studs Black Part 4276b Element 4264363 or 4256402 ×2
  • Hinge Plate 1 x 2 with 3 Fingers On Side Black Part 2452 Element 245226 ×2
  • Hinge Vehicle Roof Holder 1 x 4 Black Part 4315 Element 4250225 or 431576 ×2
  • Turntable 4 x 4 Square Base with Top, Complete Assembly Black Part 3403c01 Element 4221663 or 4143677 ×2
  • Hinge Plate 1 x 2 with 3 Fingers [Hollow Studs] Blue Part 4275b Element 4239024 or 427523 ×2

Bars, Ladders and Fences 11 pieces

  • Lever Small Base with Black Lever Light Gray Part 298c02 Element 73588 ×2
  • Antenna 8H Whip Trans-Neon Green Part 2569 Element 6265159 or 6164380 ×9

Bricks Special 9 pieces

  • Bracket 5 x 2 x 2 1/3 with Holes, Smooth Bottom Black Part 6087 Element 4100423 or 608726 ×1
  • Brick 2 x 4 x 2 with Holes on Sides Black Part 6061 ×1
  • Brick Special 1 x 1 with Headlight Black Part 4070 Element 407026 ×4
  • Brick Special 1 x 1 Studs on 4 Sides Light Gray Part 4733 Element 473302 ×2
  • Brick Special 2 x 2 with Pin and No Axle Hole Light Gray Part 4730 Element 473002 ×1

Bricks Round and Cones 7 pieces

  • Brick Round 2 x 2 with Axle Hole Black Part 3941 Element 614376 or 614326 ×2
  • Cone 4 x 4 x 2, Axle Hole [Plain] Black Part 3943b Element 4143243 or 394326 ×1
  • Cone 2 x 2 x 2, Open Stud Light Gray Part 3942c Element 394252 or 394202 ×2
  • Cone 1 x 1 [No Top Groove] Trans-Neon Green Part 4589 Element 618849 or 458949 ×2

Plates Wedged 7 pieces

  • Wedge Plate 3 x 4 without Stud Notches Black Part 4859 ×1
  • Wedge Plate 3 x 6 Cut Corners Black Part 2419 Element 241926 ×4
  • Wedge Plate 8 x 8 with 3 x 4 Cutout Black Part 6104 Element 610426 ×2

Technic Bricks 6 pieces

  • Technic Brick 1 x 1 with Pin Hole Black Part 6541 Element 654126 ×2
  • Technic Slope Long 1 x 6 with 3 Pin Holes Black Part 2744 Element 6311889 or 274426 ×2
  • Technic Slope Long 1 x 6 with 3 Pin Holes Light Gray Part 2744 Element 274402 ×2

Technic Pins 6 pieces

  • Technic Pin with Friction Ridges Lengthwise and Center Slots Black Part 2780 Element 4121715 or 278026 ×2
  • Technic Pin without Friction Ridges Lengthwise Light Gray Part 3673 Element 4184166 or 367302 ×4

Wheels and Tyres 6 pieces

  • Tyre 43 x 17 Black Part 3634 Element 4523564 or 363426 ×1
  • Wheel Hard Plastic Large (54mm D. x 30mm) Black Part 2515 Element 6468516 or 6097664 ×4
  • Wheel with Split Axle hole Black Part 3482 Element 4279396 or 4199226 ×1

Electronics 4 pieces

  • Battery Box, 9V Small [Complete Assembly] Black Part 4760c01 Element 4109849 ×1
  • Light Brick 1 x 4 [Two Bulbs] Black Part 4771 Element 74644 ×1
  • Wire with Brick 2 x 2 x 2/3 Pair, 15L Black Part 5306bc015 Element 75565 ×1
  • Motor, Monorail 9V with Long Couplings [Complete Assembly] White Part 2684c01b ×1

Minifig Shields, Weapons, & Tools 4 pieces

  • Weapon Gun / Torch (Space) [with Grooves] Black Part 3959 Element 4254942 or 395976 ×2
  • Weapon Gun / Torch (Space) [with Grooves] Light Gray Part 3959 Element 4254948 or 395952 ×2

Technic Bushes 4 pieces

  • Technic Bush Light Gray Part 3713 Element 4125313 or 659002 ×3
  • Technic Bush 1/2 Toothed Type II [X Opening] Light Gray Part 4265b Element 4100501 or 657702 ×1

Baseplates 3 pieces

  • Baseplate 16 x 32 Black Part 3857 Element 274826 ×2
  • Baseplate Raised 32 x 32 with Ramp and Pit, Crater Print Black Part 2552pr0002 Element 262400 ×1

Bricks Wedged 2 pieces

  • Brick Wedged, Sloped 6 x 4 Cutout, No Stud Notches Light Gray Part 6153a Element 615302 ×2

Rock 2 pieces

  • Rock Panel Rectangular 4 x 10 x 6 Dark Gray Part 6082 Element 608227 ×1
  • Rock Panel Triangular 3 x 8 x 7 Dark Gray Part 6083 Element 608327 ×1

Technic Axles 2 pieces

  • Technic Axle 10 Black Part 3737 Element 373726 ×2

Tubes and Hoses 2 pieces

  • Flexible Hose 8.5L with Tabless Ends (Ends same color as Tube) Light Gray Part 73590c01a ×2

Windscreens and Fuselage 2 pieces

  • Windscreen 10 x 4 x 2 1/3 Canopy Trans-Dark Blue Part 2507 Element 250793 or 250743 ×2

Stickers 1 piece

  • Sticker Sheet for Set 6991-1 [No Color/Any Color] Part 168285 Element 168285 ×1

Technic Steering, Suspension and Engine 1 piece

  • Technic Universal Joint 4L [Complete Assembly] Light Gray Part 9244 Element 9244 ×1

Tiles Round and Curved 1 piece

  • Tile Round 2 x 2 with Bottom Cross Black Part 4150 Element 415076 or 415026 ×1

Minifigures 4 figures

  • Spyrius Droid / Major Kartofski Minifigure, checked as a whole figure ×1
  • Unitron Minifigure, checked as a whole figure ×2
  • Unitron Chief Minifigure, checked as a whole figure ×1

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