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ETX Alien Mothership Assault

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7691 ETX Alien Mothership Assault

414 pieces in 143 part and color combinations, plus 7 minifigures.

The official piece count includes the 20 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.

Look-alike colors in this set

These parts appear in this set in two colors that are easy to confuse. If you are one short in one color, check whether it went in where the other color belongs. Each color has its own element ID in the parts list at the back of the instructions.

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Piece checklist

Black 136 pieces

  • Bar 1 x 4 x 2 Black Part 6187 Element 4141349 or 4121537 ×1
  • Brick 1 x 4 Black Part 3010 Element 301026 ×2
  • Brick 2 x 4 Black Part 3001 Element 300126 ×1
  • Brick 2 x 6 Black Part 2456 Element 4181144 or 245626 ×1
  • Brick Curved 6 x 1 Black Part 42022 Element 4160393 ×2
  • Brick Round Corner 10 x 10 with Slope 33° Edge, Axle Hole, Facet Cutout Black Part 58846 Element 6454174 or 6015466 ×6
  • Brick Sloped 2 x 2 No Studs, with 3 Side Pistons Raised Edges Black Part 30603 Element 4163524 ×3
  • Brick Sloped 45° 2 x 2 Black Part 3039 Element 303926 ×3
  • Brick Special 1 x 1 with Headlight Black Part 4070 Element 407026 ×6
  • Brick Wedged, Curved 10 x 3 Left Black Part 50955 Element 6344913 or 6106304 ×2
  • Brick Wedged, Curved 10 x 3 Right Black Part 50956 Element 6344914 or 6106305 ×2
  • Equipment Goblet / Glass Black Part 2343 Element 6247194 or 4223189 ×2
  • Handlebars Black Part 30031 Element 3003126 ×2
  • Hinge Brick 1 x 2 Locking with 2 Fingers Vertical End, 9 Teeth Black Part 30365 Element 4144502 or 4129975 ×2
  • Hinge Brick 2 x 2 Top Plate Thin Black Part 6134 Element 4124096 or 613426 ×2
  • Hinge Cylinder 1 x 2 Locking with 2 Click Fingers and Axle Hole, 9 Teeth Black Part 30553 Element 4143372 ×2
  • Hinge Plate 1 x 12 Locking with Angled Side Extensions and Tapered Ends, 7 Teeth Black Part 57906 Element 6525158 or 4636410 ×2
  • Hinge Plate 1 x 2 Locking with 2 Fingers On End, with Groove, 9 Teeth Black Part 44302a Element 4183060 ×6
  • Hinge Tile 1 x 4 Locking Dual 1 Fingers on Top [4 Locking Ridges] Black Part 44822 Element 4193108 ×1
  • Large Figure Weapon Spear, Drill with Axle and Hole Black Part 40340 Element 4507190 or 4227078 ×1
  • Launcher, Technic Competition Cannon Flat Bottom [Complete Assembly] Black Part 57796 Element 4518409 or 4499434 ×1
  • Plate 2 x 8 Black Part 3034 Element 303426 ×6
  • Plate Special 1 x 1 with Clip Light, Bar Hole [Thick Ring] Black Part 4081b Element 6281993 or 4632571 ×2
  • Plate Special 1 x 2 Side Handle [Free Ends] Black Part 2540 Element 4140588 or 254026 ×3
  • Plate Special 1 x 8 with Door Rail Black Part 4510 Element 4286009 or 451026 ×4
  • Technic Axle 1.5 with Perpendicular Axle Connector (Technic Pole Reverser Handle) Black Part 6553 Element 4107765 or 655326 ×1
  • Technic Axle 4 Black Part 3705 Element 370526 ×1
  • Technic Axle 6 Black Part 3706 Element 370626 ×1
  • Technic Axle Connector Double Flexible [Rubber] Black Part 45590 Element 4198367 ×1
  • Technic Axle and Pin Connector Angled #3 - 157.5° Black Part 32016 Element 6261386 or 4107082 ×1
  • Technic Axle and Pin Connector Perpendicular 3L with 2 Pin Holes Black Part 42003 Element 6273708 or 4200326 ×1
  • Technic Brick 1 x 14 [13 Pin Holes] Black Part 32018 Element 4107558 ×4
  • Technic Brick 1 x 4 [3 Pin Holes] Black Part 3701 Element 370126 ×3
  • Technic Brick 1 x 6 [5 Pin Holes] Black Part 3894 Element 389426 ×2
  • Technic Brick 4 x 6 with 2 x 4 Opening Black Part 32531 Element 6456527 or 4162508 ×2
  • Technic Pin Connector Round [No Slot] Black Part 75535 Element 75619 ×4
  • Technic Pin Double with Axle Hole Black Part 32138 Element 4130597 or 4119589 ×4
  • Technic Pin Long with Friction Ridges Lengthwise, 2 Center Slots Black Part 6558 Element 655826 ×7
  • Technic Pin with Friction Ridges Lengthwise and Center Slots Black Part 2780 Element 4121715 or 278026 1 spare in the box ×9
  • Technic Worm Gear Black Part 4716 Element 6037533 or 471626 ×1
  • Tile 1 x 4 with Groove Black Part 2431 Element 243126 Also in Dark Bluish Gray ×1
  • Tile Round 2 x 2 with Bottom Cross Black Part 4150 Element 415076 or 415026 ×10
  • Tile Special 1 x 1 with Clip and Straight Tips Black Part 2555 Element 255526 ×2
  • Tile Special 1 x 2 with Handle Black Part 2432 Element 243226 ×2
  • Turntable 2 x 2 Plate, Base Black Part 3680 Element 368076 or 368026 ×2
  • Wedge Plate 4 x 2 Left Black Part 41770 Element 4161332 ×2
  • Wedge Plate 4 x 2 Right Black Part 41769 Element 4160869 ×2
  • Wedge Plate 4 x 4 with 2 x 2 Cutout Black Part 43719 Element 6275401 or 4561035 ×8

Dark Bluish Gray 74 pieces

  • Brick Sloped 65° 2 x 2 x 2 with Bottom Tube Dark Bluish Gray Part 3678b Element 4234534 or 4210760 ×2
  • Brick Special 1 x 2 with Pin Dark Bluish Gray Part 2458 Element 4211087 ×1
  • Hinge Brick 1 x 2 Locking with 1 Finger Vertical End Dark Bluish Gray Part 30364 Element 4210723 ×2
  • Hinge Plate 1 x 2 Locking with 1 Finger on Side, with Groove Dark Bluish Gray Part 44567a Element 4210892 ×6
  • Plate 1 x 10 Dark Bluish Gray Part 4477 Element 4257526 or 4210816 ×2
  • Plate 1 x 6 Dark Bluish Gray Part 3666 Element 4211056 ×2
  • Plate 2 x 3 Dark Bluish Gray Part 3021 Element 4211043 ×6
  • Plate 2 x 4 Dark Bluish Gray Part 3020 Element 4211065 ×8
  • Plate 2 x 6 Dark Bluish Gray Part 3795 Element 4211002 ×4
  • Plate 4 x 4 Dark Bluish Gray Part 3031 Element 4243831 or 4211089 ×4
  • Plate 4 x 8 Dark Bluish Gray Part 3035 Element 4211061 ×1
  • Plate 6 x 6 Dark Bluish Gray Part 3958 Element 4211134 ×1
  • Plate Round 2 x 2 with Axle Hole Type 1 (+ Opening) Dark Bluish Gray Part 4032a Element 4211042 ×4
  • Plate Special 1 x 2 with 1 Stud without Groove (Jumper) Dark Bluish Gray Part 3794a ×2
  • Technic Axle 3 with Stud Dark Bluish Gray Part 6587 Element 6587199 or 6129590 ×3
  • Technic Beam 1 x 11.5 Double Bent Thick Dark Bluish Gray Part 32009 Element 6271155 or 4210668 ×2
  • Technic Beam 1 x 7 Thick Dark Bluish Gray Part 32524 Element 4495931 or 4210752 ×1
  • Technic Brick 1 x 2 [2 Pin Holes] Dark Bluish Gray Part 32000 Element 4210762 ×4
  • Technic Pin Connector Plate 1 x 2 x 1 2/3 [Two Holes On Top] Dark Bluish Gray Part 32530 Element 4210763 ×10
  • Tile 1 x 4 with Groove Dark Bluish Gray Part 2431 Element 4211053 Also in Black ×2
  • Tile 1 x 6 with Groove Dark Bluish Gray Part 6636 Element 4210651 ×2
  • Tile Special 1 x 2 Grille with Bottom Groove Dark Bluish Gray Part 2412b Element 4210631 ×5

Light Bluish Gray 58 pieces

  • Bar 4L (Lightsaber Blade / Wand) Light Bluish Gray Part 30374 Element 6116608 or 4211628 ×2
  • Brick 1 x 1 Light Bluish Gray Part 3005 Element 4211389 ×4
  • Brick 1 x 6 Light Bluish Gray Part 3009 Element 4211393 ×2
  • Brick Sloped Inverted 45° 2 x 2 [Ovoid Bottom Pin, Bar-sized Stud Holes] Light Bluish Gray Part 3660 Element 4211436 ×2
  • Brick Special 1 x 2 with Pin Light Bluish Gray Part 2458 Element 4211364 ×2
  • Brick Special 1 x 4 with Groove Light Bluish Gray Part 2653 Element 4211613 ×2
  • Hinge Brick 1 x 2 Base Light Bluish Gray Part 3937 Element 4211469 ×2
  • Hinge Plate 1 x 4 Swivel Top / Base - Solid Clip [Complete Assembly] Light Bluish Gray Part 73983 Element 6102769 or 4219256 ×4
  • Plate 2 x 2 Light Bluish Gray Part 3022 Element 4211397 ×10
  • Plate 2 x 8 Light Bluish Gray Part 3034 Element 4211406 ×2
  • Plate Special 2 x 2 with Grills Light Bluish Gray Part 41862 Element 4211748 ×2
  • Projectile, Technic Competition Arrow, Liftarm Shaft with Hollow Black Rubber End Light Bluish Gray Part 57028c01 Element 4299625 ×1
  • Technic Axle 3 Light Bluish Gray Part 4519 Element 4211815 ×2
  • Technic Beam 1 x 5 Thick Light Bluish Gray Part 32316 Element 4211651 ×2
  • Technic Beam 2 x 4 L-Shape Thick Light Bluish Gray Part 32140 Element 6271831 or 4211610 ×1
  • Technic Brick 1 x 2 [1 Pin Hole] Light Bluish Gray Part 3700 Element 4211440 ×4
  • Technic Bush Light Bluish Gray Part 3713 Element 6275844 or 6271817 1 spare in the box ×2
  • Technic Bush 1/2 Smooth with Axle Hole Semi-Reduced Light Bluish Gray Part 32123b Element 6271165 or 4211573 1 spare in the box ×3
  • Technic Pin 1/2 without Friction Ridges Light Bluish Gray Part 4274 Element 4274194 or 4211483 ×3
  • Technic Pin Long with Friction Ridges Lengthwise and Stop Bush [3 Lateral Holes, Big Pin Hole] Light Bluish Gray Part 32054 Element 4211865 ×2
  • Technic Plate Rotor 3 Blade with Smooth Ends and 6 Studs (Propeller) Light Bluish Gray Part 32125 Element 4262978 or 4211842 ×2
  • Turntable 2 x 2 Plate - Top Light Bluish Gray Part 3679 Element 4540203 or 4495467 ×2

White 36 pieces

  • Brick 1 x 2 White Part 3004 Element 6548257 or 4613964 ×1
  • Brick 1 x 4 White Part 3010 Element 6550135 or 301001 ×3
  • Brick 2 x 3 White Part 3002 Element 6550133 or 300251 ×1
  • Brick Arch 1 x 4 x 2 White Part 6182 Element 6031098 or 618201 ×1
  • Brick Round 2 x 2 with Axle Hole White Part 3941 Element 6601920 or 614351 ×2
  • Brick Round 2 x 2 x 2 Robot Body, Axle Holder 'X' Orientation White Part 30361b ×2
  • Brick Sloped 45° 2 x 1 with Bottom Pin White Part 3040b Element 6552115 or 4121932 ×4
  • Brick Sloped 45° 2 x 2 with Radar Screen Print White Part 3039pr0005 Element 4261941 or 82024 ×1
  • Brick Wedged, Curved 12 x 3 Left White Part 42061 Element 6021069 or 4162781 ×1
  • Brick Wedged, Curved 12 x 3 Right White Part 42060 Element 6021071 or 4162779 ×1
  • Launcher, Aero Tube Air Pump 16 x 14 x 13 [Complete Assembly] White Part 30584c01 Element 4504246 ×1
  • Panel 1 x 2 x 1 [Square Corners] White Part 4865a Element 486501 ×1
  • Plate 1 x 4 White Part 3710 Element 6552108 or 6548266 ×1
  • Plate 2 x 4 White Part 3020 Element 6552098 or 302001 ×3
  • Plate 4 x 4 White Part 3031 Element 6552127 or 4243812 ×5
  • Seat / Chair 2 x 2 White Part 4079 ×2
  • Technic Axle and Pin Connector Angled #1 White Part 32013 Element 6332573 or 4118981 ×1
  • Technic Brick 1 x 14 [13 Pin Holes] White Part 32018 Element 4161723 or 4112515 ×3
  • Technic Brick 1 x 2 [2 Pin Holes] White Part 32000 Element 6564911 or 3200001 ×1
  • Tile Special 1 x 2 with Handle White Part 2432 Element 243201 ×1

Trans-Neon Green 30 pieces

  • Antenna 1 x 4 with Rounded Top Trans-Neon Green Part 3957a ×8
  • Brick Round 2 x 2 with Axle Hole Trans-Neon Green Part 3941 Element 6273157 or 611649 ×2
  • Cone 1 x 1 [No Top Groove] Trans-Neon Green Part 4589 Element 618849 or 458949 ×8
  • Dish 6 x 6 Inverted, Radar / Webbed [Anti-studs at 90°] Trans-Neon Green Part 4285b Element 4508052 or 4110049 ×2
  • Plate Round 1 x 1 with Solid Stud Trans-Neon Green Part 6141 Element 6240223 or 3005749 1 spare in the box ×4
  • Rock 1 x 1 Jewel / Gem 24 Facet Trans-Neon Green Part 30153 Element 6247790 or 4114505 ×6

Lime 19 pieces

  • Animal Body Part / Plant, Tail / Claw / Horn / Branch / Tentacle, End Section Lime Part 40379 Element 6293393 or 6172469 ×6
  • Animal Body Part / Plant, Tail / Neck / Branch / Trunk, Middle Section with Pin, Round Pin Hole Lime Part 40378 Element 6290985 or 4650634 ×8
  • Hinge Plate 1 x 12 Locking with Angled Side Extensions and Tapered Ends, 7 Teeth Lime Part 57906 Element 6448751 or 4656148 ×2
  • Plate Round Corner 4 x 4 Lime Part 30565 Element 4504705 ×2
  • Technic Axle Connector Ridged [with x Hole x Orientation] Lime Part 6538b Element 4265703 or 4154499 ×1

Blue 13 pieces

  • Lever Small Base with Black Lever Blue Part 298c02 Element 4296152 or 4163988 1 spare in the box ×2
  • Projectile, Weapon Foam Dart with Black Tip Blue Part 58842 Element 4501928 ×4
  • Technic Axle Pin with Friction Ridges Lengthwise Blue Part 43093 Element 4309323 or 4206482 ×7

Red 12 pieces

  • Animal Body Part, Barb / Claw / Tooth / Talon / Horn, Small Red Part 53451 Element 6270107 or 4568388 1 spare in the box ×2
  • Hinge Brick 1 x 2 Locking with 1 Finger Horizontal End Red Part 30541 Element 4507196 or 4183012 ×4
  • Plate 1 x 2 Red Part 3023 Element 302321 ×1
  • Technic Axle 2 Notched Red Part 32062 Element 4142865 1 spare in the box ×3
  • Technic Pin Long with Friction Ridges Lengthwise and Stop Bush [3 Lateral Holes, Big Pin Hole] Red Part 32054 Element 4140806 or 4125198 ×2

Trans-Red 8 pieces

  • Cone 1 x 1 [No Top Groove] Trans-Red Part 4589 Element 618841 ×8

Green 6 pieces

  • Technic Brick 1 x 2 with Axle Hole Type 2 [X Opening] Green Part 32064b ×6

Orange 6 pieces

  • Flexible Ribbed Hose 8mm Ends 19L Orange Part 57539 Element 4561469 or 4508092 ×3
  • Launcher, Weapon, Four Barrel Foam Dart Launcher Orange Part 59492 Element 4505526 ×1
  • Tile Special 1 x 2 Grille with Bottom Groove Orange Part 2412b Element 4125254 or 3933106 ×2

Trans-Dark Blue 6 pieces

  • Cone 1 x 1 [No Top Groove] Trans-Dark Blue Part 4589 Element 618843 ×2
  • Plate Round 1 x 1 with Solid Stud Trans-Dark Blue Part 6141 Element 6514055 or 6240214 1 spare in the box ×4

Bright Green 4 pieces

  • Technic Rubber Belt Medium [24mm ID] [Round Cross Section] Bright Green Part 85544 ×4

Trans-Clear 4 pieces

  • Aero Tube Joiner 3 x 4 x 3 Trans-Clear Part 30585b Element 4506997 ×2
  • Brick Round 2 x 2 x 1 2/3 Dome Top, Blocked Open Stud Trans-Clear Part 30151a Element 4113949 ×2

Trans-Orange 1 piece

  • Aero Tube 32 x 3 x 2 1/3 Trans-Orange Part 23221 Element 4505360 ×1

[No Color/Any Color] 1 piece

  • Sticker Sheet for Set 7691-1 [No Color/Any Color] Part 59623 Element 4506056 ×1

Minifigures 7 figures

  • Martian Minifigure, checked as a whole figure ×5
  • Mars Astronaut, Printed Hair Minifigure, checked as a whole figure ×1
  • Mars Astronaut, Stubble, Printed Hair over Eyes Minifigure, checked as a whole figure ×1

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

When a piece really is missing

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