LEGO 3804
Robotics Invention System, Version 2.0

LEGO 3804 Robotics Invention System, Version 2.0 box image
Set number
3804
Theme
RCX
Pieces
720 pcs
Year
2001
Used avg¥31,037as of 7/24
Used & parts
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“Robotics Invention System, Version 2.0” is LEGO® “RCX” theme set number 3804. Released in 2001, it has 720 pieces. With Re:GO you can automatically work out what percentage of this set you can build from the LEGO parts you already own, along with the missing parts and an estimated cost. Use the links below to compare prices on Amazon, Rakuten, Yahoo! Shopping, Mercari and Yahoo! Auctions, and find the best deal on new, used, or individual parts.

Part breakdown 144 types

Color split (most first)
Light Gray×304
Black×270
Yellow×46
White×24
Blue×24
Dark Gray×21
Green×14
Trans-Dark Blue×4
Dark Turquoise×4
Purple×4
[No Color/Any Color]×2
Trans-Neon Orange×2
Main parts (most used first)
3713 Technic Bush
Light Gray · ×40
2780 Technic Pin with Friction Ridges Lengthwise and Center Slots
Black · ×24
3673 Technic Pin without Friction Ridges Lengthwise
Light Gray · ×24
3003 Brick 2 x 2
Black · ×20
3004 Brick 1 x 2
Black · ×20
3023 Plate 1 x 2
Light Gray · ×20
32123a Technic Bush 1/2 Smooth with Axle Hole Reduced
Light Gray · ×18
32002 Technic Pin 3/4
Dark Gray · ×16
3749 Technic Axle Pin without Friction Ridges Lengthwise
Light Gray · ×16
3040b Slope 45° 2 x 1 with Bottom Pin
Black · ×12
3700 Technic Brick 1 x 2 [1 Pin Hole]
Black · ×12
32062 Technic Axle 2 Notched
Black · ×10
3666 Plate 1 x 6
Light Gray · ×10
3701 Technic Brick 1 x 4 [3 Pin Holes]
Black · ×10
3710 Plate 1 x 4
Light Gray · ×10
2420 Plate 2 x 2 Corner
Light Gray · ×8
2730 Technic Brick 1 x 10 [9 Pin Holes]
Black · ×8
3022 Plate 2 x 2
Light Gray · ×8
3024 Plate 1 x 1
Light Gray · ×8
32028 Plate Special 1 x 2 with Door Rail
Light Gray · ×8
3460 Plate 1 x 8
Light Gray · ×8
3702 Technic Brick 1 x 8 [7 Pin Holes]
Black · ×8
3706 Technic Axle 6
Black · ×8
3738 Technic Plate 2 x 8 [7 Holes]
Light Gray · ×8

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