Skip to content
Back of the Box Builds

Back of the Box Builds

LEGO Alternate Builds!

  • SETS
    • Adventurers
    • Aquazone
    • Belville
    • BATMAN™
    • BIONICLE
    • Building Set with People
    • Castle
    • Duplo
    • Fabuland
    • Harry Potter
    • Holiday and Event
    • LEGOLAND
    • Model Team
    • Pirates
    • Space
    • Star Wars
    • Technic
    • Train
    • Town
    • Universal Building Set
    • Western
    • More Sets
    • Misc
  • USEFUL LINKS
    • Submit Instructions!
    • New Instructions
    • New Official Sets
    • New Alternate Builds
    • Minifigs
    • Very Small Builds
    • Small Builds
    • Medium Builds
    • Large Builds
    • Extra Large Builds
    • How BOTBB was Built
  • THIS IS AN INDEPENDENT SITE NOT AUTHORIZED OR SPONSORED BY THE LEGO GROUP
Alternate Builds Instructions Added Large Alt Build Large Builds Model Team Model Team Alternate Builds 

5521 – Back A

January 29, 2026March 4, 2026 Master Builder 4612 Views

From: 5521: Sea Jet
Name: TBD 1
Instructions: View PDF | Download .io File

Contributions

  1. Name, PDF and .io file submitted on January 29, 2026 by: livi
  • ← Space Skeletal Horse Concept
  • 5581 – Back A →

You May Also Like

6956 – Back A

September 23, 2019October 25, 2021 Master Builder

1195 – Back A

August 5, 2023August 5, 2023 Master Builder

6258 – Back B

July 8, 2022July 12, 2022 Master Builder

6336 – Back C

July 12, 2021July 12, 2021 Master Builder

2846 – Back A

October 10, 2023October 10, 2023 Master Builder

1694 – Back A

February 9, 2021March 14, 2025 Master Builder

EXPLORE MORE OFFICIAL SETS

7708: Uplink
Exo-Force Official Sets Small Builds 

7708: Uplink

August 11, 2023August 11, 2023 Master Builder

Year Released: 2006BricklinkInstructions

9401: M:Tron Team
Bonus/Value Pack Sets Bonus/Value Packs M:Tron M:Tron Sets Official Sets Space Very Small Builds 

9401: M:Tron Team

February 18, 2026March 7, 2026 Master Builder
6848: Strategic Pursuer
Bjarne Tveskov Duplicate Set Number Futron Sets Futuron Official Sets Small Builds Space 

6848: Strategic Pursuer

April 16, 2021March 11, 2024 Master Builder
6357: Stunt ‘Copter N’ Truck
Classic Town Medium Builds Official Sets Town Town Sets Traffic 

6357: Stunt ‘Copter N’ Truck

January 28, 2022January 28, 2022 Master Builder
6581: Dig N’ Dump
Classic Town Construction Medium Builds Official Sets Town Town Sets 

6581: Dig N’ Dump

November 7, 2022November 7, 2022 Master Builder
6389: Fire Control Center
Classic Town Extra Large Builds Fire Official Sets Town Town Sets 

6389: Fire Control Center

January 24, 2022January 24, 2022 Master Builder
6379: Riding Stable
Building Classic Town Large Builds Official Sets Town Town Sets 

6379: Riding Stable

February 8, 2022February 8, 2022 Master Builder
8593: Makuta
Alternate Instructions Included BIONICLE BIONICLE Sets Instructions Added Medium Alt Build Medium Builds Official Sets Titans 

8593: Makuta

April 23, 2026April 23, 2026 Master Builder
6589: Radical Racer {with Rocky Ridge Playscape}
Box Plus Extreme Team Official Sets Playscape/Play Stage Box Small Builds Town Town Sets 

6589: Radical Racer {with Rocky Ridge Playscape}

February 27, 2023October 8, 2024 Master Builder
6905: Bi-Wing Blaster
Insectoids Insectoids Sets Official Sets Small Builds 

6905: Bi-Wing Blaster

February 22, 2023February 22, 2023 Master Builder
6890: Cosmic Cruiser
Classic Space Classic Space Sets Medium Builds Official Sets 

6890: Cosmic Cruiser

October 7, 2019October 7, 2019 Master Builder
2846: Indian Kayak
Indians Official Sets Very Small Builds Western Western Sets 

2846: Indian Kayak

October 10, 2023October 10, 2023 Master Builder
6852: Sonar Security
Jørn Thomsen Official Sets Small Builds Space Space Police II Space Police II Sets 

6852: Sonar Security

September 22, 2020July 29, 2023 Master Builder
7314: Recon-Mech RP
Life on Mars Life on Mars Sets Medium Builds Official Sets Space 

7314: Recon-Mech RP

July 14, 2021July 14, 2021 Master Builder
6350: Pizza To Go
Classic Town Food and Drink Medium Builds Official Sets Town Town Sets 

6350: Pizza To Go

April 9, 2020February 3, 2021 Master Builder
6673: Solo Trainer
Airport Classic Town Medium Builds Official Sets Town Town Sets 

6673: Solo Trainer

November 18, 2020November 18, 2020 Master Builder

BOXES

INSTRUCTIONS

FAVORITES

MINIFIGS

About This Site

Logo
There were once pictures of additional LEGO® builds on the back of set boxes. Written on the boxes was typically something about the endless building possibilities, "Build any of these exciting models with this set!" There were no instructions for these alternate builds, until now.

Sets

  • Adventurers
  • Aquazone
  • BATMAN
  • Bionicle
  • Belville
  • Building Set with People
  • Castle
  • Duplo
  • Fabuland
  • Harry Potter
  • Holiday and Event
  • LEGOLAND
  • Model Team
  • Pirates
  • Space
  • Star Wars
  • Technic
  • Train
  • Town
  • Universal Building Set
  • Western
  • More Sets
  • Misc

Useful Links

  • Submit Instructions!
  • New Instructions
  • New Official Sets
  • New Alternate Builds
  • Minifigs
  • Very Small Builds (<35 pcs)
  • Small Builds (<100 pcs)
  • Medium Builds (<200 pcs)
  • Large Builds (<400 pcs)
  • Extra Large Builds (>400 pcs)
  • How BOTBB was Built

In Honor of 1526

The classic space set that never was.

Copyright © 2026 Back of the Box Builds. All rights reserved. LEGO® is a trademark of the LEGO Group of companies which does not sponsor, authorize, or endorse this site.