B543 Extra Light Torque Tube Type Airframe Control Bearing 1.5625" x 2" x 0.281"B543 Extra Light Torque Tube Bearing 1. 5625" x 2" x 0. 281" Full Complement For Non Aircraft Use The B543 is a single row, extra light duty torque tube bearing designed for control systems, linkages, or mechanical assemblies where low weight and compact size matter. With a full complement of 44 balls and no cage, it offers maximum contact for better load support in tight spaces. Built from chromium alloy, high carbon steel and preserved for storage