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Amazon.com: LEGO® Technic Heavy-Duty Excavator 42121 Toy Building Kit; A Cool Birthday;Construction Toys : Toys & Games
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LEGO Heavy Duty Excavator vs LEGO Excavator | LEGO 42121 vs 42006 | LEGO 42006 vs 42121 | Compare - YouTube
![Lego 42121 - C model Bulldozer - LEGO Technic, Mindstorms, Model Team and Scale Modeling - Eurobricks Forums Lego 42121 - C model Bulldozer - LEGO Technic, Mindstorms, Model Team and Scale Modeling - Eurobricks Forums](https://live.staticflickr.com/65535/51078642093_c3345e62f8_c.jpg)
Lego 42121 - C model Bulldozer - LEGO Technic, Mindstorms, Model Team and Scale Modeling - Eurobricks Forums
![Turning lego set 42121 into a crawler crane, I'm waiting for more parts, but this is what I have so far! : r/legotechnic Turning lego set 42121 into a crawler crane, I'm waiting for more parts, but this is what I have so far! : r/legotechnic](https://i.redd.it/1mrqn4tqw1l61.jpg)
Turning lego set 42121 into a crawler crane, I'm waiting for more parts, but this is what I have so far! : r/legotechnic
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MOD] 42121 Compact Excavator - LEGO Technic, Mindstorms, Model Team and Scale Modeling - Eurobricks Forums
![42121 - Heavy-Duty Excavator - Building Instructions : Free Download, Borrow, and Streaming : Internet Archive 42121 - Heavy-Duty Excavator - Building Instructions : Free Download, Borrow, and Streaming : Internet Archive](https://archive.org/download/lego-building-instructions-42121/42121_01_Build_Alt.png)