LEGO® Part 3941 - Brick, Round 2 x 2 with Axle Hole

The LEGO® Round Brick 2 x 2 with Axle Hole (Design ID 3941) is a versatile cylindrical building element that combines the appearance of a standard round brick with a central Technic-compatible axle hole. Available in multiple colour variants on this page, it is widely used for wheels, machinery, towers, engines, decorative details and custom LEGO® MOCs where both strength and rotational functionality are required.

Technical Specifications

• Part Name: Round Brick 2 x 2 with Axle Hole
• Design ID: 3941
• Size: 2 x 2 studs
• Feature: Central axle hole
• Type: Cylindrical round brick

Building with LEGO® Round Brick 3941

The integrated axle hole makes this part especially useful for functional builds. It can support rotating mechanisms, wheel hubs, decorative columns, machinery, engines and countless mechanical assemblies while maintaining the clean appearance of a round brick. Its larger 2 x 2 footprint also provides additional stability compared with smaller cylindrical elements.

This combination of structural strength and mechanical compatibility has made Design ID 3941 a popular component across many official LEGO® sets as well as advanced custom creations.

Explore More LEGO® Round Building Elements

Browse our complete LEGO® Round Bricks collection for cylindrical building elements of every size, or explore our full range of LEGO® Bricks. Builders creating curved designs may also be interested in our LEGO® Macaroni Bricks and LEGO® Dome Bricks. For smaller cylindrical details, see the LEGO® Round Brick 1 x 1 (3062).