Building a fast Lego motorboat with two submerged Lego propellers. Only Lego parts are used, except for a BuWizz 3.0 battery box. Enjoy!

Battery box: BuWizz 3.0 Pro https://buwizz.com/shop/buwizz-3-0-pro/?ref=212
Motors: 2x Lego Buggy motor 5292c01 https://www.bricklink.com/v2/catalog/catalogitem.page?P=5292c01
Propellers: 2x Lego Propeller 2 Blade Twisted 4745 https://www.bricklink.com/v2/catalog/catalogitem.page?P=4745
Propeller attachment: double-sided tape rolled on a Lego axle
Hull: Lego Hull Giant Bow 4245c01 https://www.bricklink.com/v2/catalog/catalogitem.page?P=4245c01

More details in my blog, including a part list and 3D model for the motorboat:

Fast RC Lego Boats – blog post series