Brick, Hinge 1 x 4 Swivel Base (3831)

The 1 x 4 hinge brick base (Part 3831) is the foundational lower half of a swivel joint assembly. It features a circular pivot pin designed to connect with a swivel top (Part 3830), enabling smooth horizontal rotation. This element is essential for building articulating vehicle sections, rotating display platforms, or folding wall segments in structural projects.

Discover more in our Hinge Pieces collection.

LEGO® parts are intended for builders aged 4 and up. They may pose a choking hazard for children under 3 years old.