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Bikini Bottom Undersea Party

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3818 Bikini Bottom Undersea Party

459 pieces in 169 part and color combinations, plus 4 minifigures.

The official piece count includes the 12 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

Bricks Sloped 77 pieces

  • Brick Sloped Inverted 45° 2 x 1 Blue Part 3665 Element 366523 ×1
  • Brick Sloped Inverted 45° 2 x 1 Dark Bluish Gray Part 3665 Element 4211096 ×2
  • Brick Sloped Inverted 45° 2 x 2 [Ovoid Bottom Pin, Bar-sized Stud Holes] Dark Bluish Gray Part 3660 Element 4211000 ×2
  • Brick Sloped 30° 1 x 1 x 2/3 (Cheese Slope) Light Bluish Gray Part 54200 Element 4521921 or 4244372 1 spare in the box ×6
  • Brick Sloped 33° 3 x 1 Light Bluish Gray Part 4286 Element 4211488 ×2
  • Brick Sloped 45° 2 x 1 with Bottom Pin Light Bluish Gray Part 3040b Element 4211614 ×2
  • Brick Sloped 65° 2 x 2 x 2 with Bottom Tube Light Bluish Gray Part 3678b Element 4234535 or 4215353 ×6
  • Brick Sloped 75° 2 x 2 x 3 Double Convex Light Bluish Gray Part 3685 Element 6392265 or 4541262 ×2
  • Brick Sloped 30° 1 x 1 x 2/3 (Cheese Slope) Medium Blue Part 54200 Element 4565363 1 spare in the box ×4
  • Brick Sloped 30° 1 x 1 x 2/3 (Cheese Slope) Orange Part 54200 Element 4504371 or 4248195 1 spare in the box ×16
  • Brick Sloped 45° 2 x 1 Triple with Ovoid Bottom Pin Orange Part 3048c Element 4655149 or 4540238 ×10
  • Brick Sloped 45° 2 x 2 Orange Part 3039 Element 4118828 ×2
  • Brick Sloped 75° 2 x 1 x 3 with Hollow Stud Orange Part 4460b Element 6549658 or 4295307 ×8
  • Brick Sloped Inverted 45° 2 x 1 Orange Part 3665 Element 4616279 or 4515954 ×2
  • Brick Sloped Inverted 45° 2 x 2 [Ovoid Bottom Pin, Bar-sized Stud Holes] Orange Part 3660 Element 4118829 ×4
  • Brick Sloped Inverted 75° 2 x 1 x 3 Orange Part 2449 Element 4159199 ×8

Bricks 70 pieces

  • Brick 1 x 1 Blue Part 3005 Element 300523 ×2
  • Brick 1 x 2 Blue Part 3004 Element 4613959 or 300423 ×6
  • Brick 1 x 3 Blue Part 3622 Element 362223 ×2
  • Brick 1 x 4 Blue Part 3010 Element 301023 ×2
  • Brick 2 x 2 Dark Blue Part 3003 Element 4296785 or 4264580 ×1
  • Brick 1 x 2 x 5 with Blocked Open Studs and Bottom Stud Holder with Asymmetric Ridges Dark Bluish Gray Part 2454a ×4
  • Brick 1 x 1 Light Bluish Gray Part 3005 Element 4211389 ×3
  • Brick 1 x 1 x 5 with Solid Stud Light Bluish Gray Part 2453b Element 4211362 ×1
  • Brick 1 x 2 Light Bluish Gray Part 3004 Element 4211388 ×6
  • Brick 1 x 2 x 2 with Inside Stud Holder Light Bluish Gray Part 3245c Element 4211564 ×6
  • Brick 1 x 4 Light Bluish Gray Part 3010 Element 4211394 ×5
  • Brick 2 x 2 Light Bluish Gray Part 3003 Element 4211387 ×1
  • Brick 2 x 2 x 3 Light Bluish Gray Part 30145 Element 4211650 ×4
  • Brick 2 x 4 Light Bluish Gray Part 3001 Element 4211385 ×2
  • Brick 1 x 1 Orange Part 3005 Element 4173805 or 4119645 ×9
  • Brick 1 x 2 Orange Part 3004 Element 4613981 or 4121739 ×8
  • Brick 1 x 3 Orange Part 3622 Element 4118787 ×2
  • Brick 1 x 4 Orange Part 3010 Element 4118827 ×4
  • Brick 1 x 1 x 5 with Solid Stud Reddish Brown Part 2453b Element 4226966 ×2

Plates 59 pieces

  • Plate 1 x 2 Blue Part 3023 Element 302323 ×6
  • Plate 2 x 3 Dark Bluish Gray Part 3021 Element 4211043 ×5
  • Plate 2 x 8 Dark Bluish Gray Part 3034 Element 4210997 ×1
  • Plate 4 x 8 Dark Bluish Gray Part 3035 Element 4211061 ×1
  • Plate 1 x 2 Lime Part 3023 Element 4164037 or 4122439 ×1
  • Plate 1 x 6 Orange Part 3666 Element 4173332 or 4122466 ×4
  • Plate 2 x 4 Orange Part 3020 Element 4158355 or 4122468 ×2
  • Plate 1 x 2 Red Part 3023 Element 302321 ×8
  • Plate 1 x 6 Red Part 3666 Element 366621 ×2
  • Plate 2 x 10 Red Part 3832 Element 383221 ×1
  • Plate 2 x 2 Red Part 3022 Element 4613974 or 302221 ×4
  • Plate 1 x 4 Reddish Brown Part 3710 Element 4211190 ×3
  • Plate 2 x 4 Reddish Brown Part 3020 Element 4211186 ×5
  • Plate 2 x 6 Reddish Brown Part 3795 Element 4211247 ×2
  • Plate 2 x 3 Tan Part 3021 Element 4118790 or 302105 ×2
  • Plate 2 x 6 Tan Part 3795 Element 4113993 or 379505 ×5
  • Plate 4 x 6 Tan Part 3032 Element 4114001 ×5
  • Plate 6 x 10 Tan Part 3033 Element 4624185 or 4218966 ×1
  • Plate 1 x 1 White Part 3024 Element 6548262 or 302401 ×1

Plates Round Curved and Dishes 58 pieces

  • Dish 2 x 2 Inverted [Radar] Black Part 4740 Element 474026 ×4
  • Plate Round 1 x 1 with Solid Stud Black Part 6141 Element 614126 ×2
  • Dish 3 x 3 Inverted [Radar] Blue Part 43898 Element 6311454 or 6195819 ×2
  • Plate Round 2 x 2 with Rounded Bottom [Boat Stud] Blue Part 2654 Element 4278276 or 4208686 ×6
  • Dish 2 x 2 Inverted [Radar] with Dark Red Swirl and Medium Blue Spots Print Bright Pink Part 4740pr0016 Element 4541082 ×2
  • Plate Round 4 x 4 with Pin Hole Dark Bluish Gray Part 60474 Element 4528323 ×1
  • Plate Round 1 x 1 with Solid Stud Flat Silver Part 6141 Element 4633691 2 spares in the box ×5
  • Plate Round 1 x 1 with Solid Stud Lime Part 6141 Element 4183133 ×4
  • Dish 8 x 8 Inverted [Radar], Solid Studs, Rounded Anti-stud Underside Orange Part 3961 Element 4288162 ×1
  • Plate Round 1 x 1 with Solid Stud Orange Part 6141 Element 4157103 1 spare in the box ×15
  • Plate Round 1 x 1 with Solid Stud Pearl Gold Part 6141 Element 4523159 2 spares in the box ×4
  • Dish 3 x 3 Inverted [Radar] Red Part 43898 Element 6365073 or 4179584 ×1
  • Plate Round Corner 3 x 3 Red Part 30357 Element 4178428 or 3035721 ×4
  • Plate Round 2 x 2 with Axle Hole Type 1 (+ Opening) Reddish Brown Part 4032a Element 4211159 ×1
  • Plate Round 2 x 2 with Rounded Bottom [Boat Stud] Trans-Clear Part 2654 Element 6581772 or 6163901 ×2
  • Plate Round 1 x 1 with Solid Stud Trans-Light Blue Part 6141 Element 6514058 or 6240225 1 spare in the box ×2
  • Plate Round 1 x 1 with Solid Stud Trans-Yellow Part 6141 Element 6514056 or 6240216 1 spare in the box ×1
  • Plate Round 2 x 2 with Axle Hole Type 1 (+ Opening) White Part 4032a Element 6601914 or 403201 ×1

Plates Special 34 pieces

  • Plate Special 1 x 2 with 1 Stud with Groove (Jumper) Black Part 3794b Element 379426 ×1
  • Plate Special 1 x 1 with Clip Vertical [Thick U Clip] Blue Part 4085c Element 408523 ×2
  • Plate Special 2 x 2 with Groove and Center Stud (Jumper) Dark Blue Part 87580 Element 6389696 or 4565320 ×1
  • Plate Special 1 x 2 with 1 Stud with Groove (Jumper) Green Part 3794b Element 379428 ×1
  • Bracket 1 x 2 - 1 x 4 [Square Corners] Light Bluish Gray Part 2436 Element 4282740 or 4211358 ×1
  • Plate Special 1 x 2 with Door Rail Light Bluish Gray Part 32028 Element 4211568 ×2
  • Plate Special 2 x 2 with 2 Pin Holes Light Bluish Gray Part 2817 Element 4211376 ×2
  • Plate Special 2 x 2 with Groove and Center Stud (Jumper) Medium Blue Part 87580 Element 6126060 or 4581079 ×6
  • Plate Special 1 x 2 [Side Handle Closed Ends] Red Part 48336 Element 4226876 ×5
  • Plate Special 1 x 2, Top Clip [Split] Red Part 92280 Element 4597713 ×12
  • Plate Special 1 x 1 with Clip Vertical [Thick U Clip] White Part 4085c Element 408501 ×1

Hinges, Arms and Turntables 29 pieces

  • Hinge Brick 2 x 2 Top Plate Thin Black Part 6134 Element 4124096 or 613426 ×2
  • Hinge Cylinder 1 x 2 Locking with 1 Finger and Axle Hole On Ends Black Part 30552 Element 4158848 ×1
  • Hinge Plate 1 x 2 Locking with 2 Fingers on Side, 9 Teeth Black Part 60471 Element 4515340 ×1
  • Turntable 4 x 4 Square Base, Locking Black Part 61485 Element 4517986 ×1
  • Hinge Brick 1 x 4 [Lower] Blue Part 3831 Element 6320053 or 383123 ×1
  • Hinge Brick 1 x 4 [Upper] Blue Part 3830 Element 6392876 or 6320054 ×1
  • Turntable 2 x 2 Plate, Base Blue Part 3680 Element 368023 ×2
  • Hinge Brick 1 x 2 Base Dark Bluish Gray Part 3937 Element 4211066 ×2
  • Turntable 2 x 2 Plate - Top Light Bluish Gray Part 3679 Element 4540203 or 4495467 ×2
  • Hinge Brick 1 x 4 [Lower] Red Part 3831 Element 6512257 or 6397573 ×4
  • Hinge Brick 1 x 4 [Upper] Red Part 3830 Element 6397607 or 6011464 ×4
  • Hinge Plate 1 x 4 Swivel Top / Base - Solid Clip [Complete Assembly] Red Part 73983 Element 6102786 or 74230 ×8

Tiles 22 pieces

  • Tile 1 x 2 with Groove Blue Part 3069b Element 306923 ×1
  • Tile 1 x 4 with Groove Dark Brown Part 2431 Element 6313874 or 4536989 ×2
  • Tile 1 x 2 with Groove Light Bluish Gray Part 3069b Element 4211414 ×2
  • Tile 1 x 2 with Stylised Computer Console Print Light Bluish Gray Part 3069bpr0086 Element 4212363 ×1
  • Tile 1 x 2 with Groove Medium Blue Part 3069b Element 4168345 ×7
  • Tile 2 x 2 with Groove Orange Part 3068b Element 4542142 or 4125268 ×3
  • Tile 2 x 2 with Groove Reddish Brown Part 3068b Element 4271949 or 4264030 ×2
  • Tile 1 x 3 White Part 63864 Element 6552134 or 6548270 ×2
  • Tile 2 x 2 with Groove White Part 3068b Element 6548263 or 306801 ×2

Bricks Round and Cones 14 pieces

  • Brick Round 1 x 1 Open Stud Blue Part 3062b Element 306223 ×2
  • Brick Round 2 x 2 with Axle Hole Blue Part 3941 Element 614373 or 614323 ×1
  • Cone 2 x 2 x 2, Open Stud Blue Part 3942c Element 6092663 or 6022149 ×1
  • Brick Round 2 x 2 Dome Top, Blocked Open Stud, Bottom Axle Holder Dark Green Part 30367b ×1
  • Brick Round 2 x 2 Dome Top, Blocked Open Stud, Bottom Axle Holder Red Part 30367b Element 4185891 ×2
  • Cone 1 x 1 [Top Groove] Reddish Brown Part 59900 Element 4529242 ×1
  • Brick Round 1 x 1 Open Stud Tan Part 3062b Element 4117070 or 306205 ×3
  • Brick Round 2 x 2 [Grill] Tan Part 92947 Element 4650647 or 4612717 ×1
  • Brick Round 2 x 2 Dome Top, Blocked Open Stud, Bottom Axle Holder Yellow Part 30367b Element 4185784 ×2

Bars, Ladders and Fences 10 pieces

  • Bar 4L (Lightsaber Blade / Wand) Black Part 30374 Element 6116604 or 4140303 ×1
  • Light Cover 1 x 1 Round with Internal Bar / Bionicle Barraki Eye Trans-Red Part 58176 Element 6507867 or 6171762 ×1
  • Antenna 1 x 4 with Flat Top White Part 3957b Element 6550147 or 395701 ×1
  • Bar 1 x 6 [Closed Studs] White Part 6140 Element 4288961 or 4279386 ×1
  • Bar 4L (Lightsaber Blade / Wand) White Part 30374 Element 6116602 or 4129836 ×2
  • Bar 1 x 4 x 2 Yellow Part 6187 Element 6145160 or 4107090 ×4

Plants & Trees 10 pieces

  • Plant, Carrot Top Bright Green Part 33183 Element 4119479 2 spares in the box ×2
  • Plant, Palm Leaf Small Green Part 6148 Element 6269040 or 4258459 ×5
  • Plant, Round 1 x 1 - 3 Bamboo Leaves Green Part 30176 Element 6270003 or 6248461 ×2
  • Plant, Cherries Lime Part 22667 Element 6087084 or 6062387 1 spare in the box ×1

Plates Wedged 10 pieces

  • Wedge Plate 3 x 6 Cut Corners Orange Part 2419 Element 4544435 or 4229601 ×2
  • Wedge Plate 6 x 3 Left Orange Part 54384 Element 6099195 or 4544487 ×4
  • Wedge Plate 6 x 3 Right Orange Part 54383 Element 6099202 or 4544481 ×4

Bricks Curved 9 pieces

  • Brick Arch 1 x 6 Raised Arch Blue Part 92950 Element 6133607 or 4618877 ×2
  • Brick Curved 1 x 2 x 1 1/3 with Curved Top Blue Part 6091 Element 6347945 or 4519981 ×2
  • Brick Arch 1 x 8 x 2 Dark Bluish Gray Part 3308 Element 4541748 or 4220973 ×1
  • Brick Arch 1 x 6 Raised Arch Light Bluish Gray Part 92950 Element 4618874 ×3
  • Brick Arch 1 x 4 Red Part 3659 Element 365921 ×1

Minifig Accessories 7 pieces

  • Equipment Telescope / Torch / Spyglass, Support Round 1 x 1 x 1 2/3 Black Part 64644 Element 4538456 ×1
  • Equipment Dish / Plate / Bowl 3 x 3 [Plain] Bright Light Orange Part 6256 Element 4243920 ×1
  • Equipment Telescope / Torch / Spyglass, Support Round 1 x 1 x 1 2/3 Dark Brown Part 64644 Element 4538950 ×2
  • Equipment Cup / Mug [Plain] Trans-Clear Part 3899 Element 6514013 or 6238856 ×2
  • Food Popsicle / Lollipop Trans-Neon Green Part 30222 Element 6216057 or 4568173 ×1

Panels 7 pieces

  • Panel 1 x 2 x 1 [Rounded Corners] Black Part 4865b Element 6146220 ×1
  • Panel 1 x 4 x 3 [Side Supports / Hollow Studs] Orange Part 60581 Element 6129596 or 4558210 ×2
  • Panel 1 x 2 x 2 [Side Supports / Hollow Studs] Red Part 87552 Element 4570470 ×1
  • Panel 1 x 2 x 1 [Square Corners] Trans-Brown Part 4865a Element 4200798 ×1
  • Panel 1 x 2 x 2 with Porthole Blue on Orange Background Print Trans-Clear Part 87552pr0006 Element 6001658 ×2

Tiles Special 7 pieces

  • Tile Special 1 x 1 with Clip with Rounded Tips Light Bluish Gray Part 12825 Element 6030711 ×3
  • Tile Special 2 x 2 with Bar, Hollow Stud with Stop Ring (Flag Pole) White Part 98549 Element 6170709 or 4649222 ×1
  • Tile Special 1 x 1 with Clip with Rounded Tips Yellow Part 12825 Element 6030719 ×1
  • Tile Special 1 x 2 with Handle Yellow Part 2432 Element 243224 ×2

Bricks Special 6 pieces

  • Brick Special 1 x 1 x 3 with 2 Clips Vertical [Hollow Stud, Open O Clips] Black Part 60583b Element 6320325 or 4563681 ×1
  • Brick Special 1 x 1 with Stud on 1 Side Dark Bluish Gray Part 87087 Element 4558955 ×1
  • Brick Special 1 x 2 with Studs on 2 Sides Red Part 52107 Element 4569056 ×3
  • Brick Special 1 x 1 with Studs on 2 Sides Tan Part 47905 Element 4213568 ×1

Technic Bricks 5 pieces

  • Technic Brick 1 x 1 with Pin Hole Black Part 6541 Element 654126 ×4
  • Technic Brick 1 x 2 [1 Pin Hole] Black Part 3700 Element 370026 ×1

Technic Pins 5 pieces

  • Technic Pin with Friction Ridges Lengthwise and Towball Black Part 6628 Element 4184169 or 662826 ×1
  • Technic Axle Pin with Friction Ridges Lengthwise Blue Part 43093 Element 4309323 or 4206482 ×1
  • Technic Pin without Friction Ridges Lengthwise Light Bluish Gray Part 3673 Element 4211807 or 3673194 1 spare in the box ×2
  • Technic Pin Long without Friction Ridges Tan Part 32556 ×1

Containers 4 pieces

  • Box 2 x 2 x 2 [Hollow Studs] Red Part 4345b Element 4261628 or 434571 ×1
  • Treasure Chest Bottom with Rear Slots, with Groove Reddish Brown Part 4738b Element 4280114 or 4211162 ×2
  • Box 2 x 2 x 2 Door with Slot Trans-Clear Part 4346 Element 6499105 or 6247357 ×1

Windows and Doors 3 pieces

  • Door 1 x 4 x 6 Round Top with Window and Keyhole, Reinforced Edge Reddish Brown Part 64390 Element 4561915 ×1
  • Window 1 x 2 x 2 Flat Front Reddish Brown Part 60592 Element 6382102 or 4595814 ×2

Energy Effects 2 pieces

  • Flame / Headwear Accessory Plume / Feather, Triple Point Trans-Neon Orange Part 64647 Element 6289248 or 6100033 1 spare in the box ×2

Technic Axles 2 pieces

  • Technic Axle 2 Notched Black Part 32062 Element 4109810 or 3206226 ×2

Technic Connectors 2 pieces

  • Technic Pin Connector Plate 1 x 2 x 1 2/3 [Two Holes On Top] Black Part 32530 Element 4144024 ×2

Tiles Round and Curved 2 pieces

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

Minifig Shields, Weapons, & Tools 1 piece

  • Tool Hammer / Mallet Large Black Part 4522 Element 452226 ×1

Stickers 1 piece

  • Sticker Sheet for Set 3818-1 [No Color/Any Color] Part 72333 Element 4655091 ×1

Technic Beams 1 piece

  • Technic Beam 1 x 5 Thick White Part 32316 Element 4249021 or 4140465 ×1

Transportation - Land 1 piece

  • Seat / Chair 2 x 2 with Center Sprue Mark Blue Part 4079b Element 407923 ×1

Transportation - Sea and Air 1 piece

  • Boat / Ship Wheel / Helm with Slotted Pin Reddish Brown Part 4790b Element 6278548 or 4548857 ×1

Minifigures 4 figures

  • Mrs. Puff with Flower Minifigure, checked as a whole figure ×1
  • Patrick Star with Lei and Sunglasses Minifigure, checked as a whole figure ×1
  • SpongeBob Squarepants with Lei Minifigure, checked as a whole figure ×1
  • Squidward Tentacles with Lei 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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