For External Halyard Poles, Threaded Type, Revolving, Double Pulley. Cast aluminum construction with two 1-15/16 in. outside diameter nylon pulleys on a 1/4 in. stainless steel axle. This truck is designed to be used on flagpoles that have up to a 3-1/2 in. outside top diameter with female fitting installed. The bottom of the spindle has a 1-1/4 in. threading and is screwed into the top of the flagpole while the top spindle is designed to accept an ornament with a standard spindle threading of 1/2 in, but can be supplied with other sizes of threading. The ornament is secured to the truck with a 1/4 in. stainless steal set screw. For ease of rotation, product life and strength, these trucks utilize self-lubrication ball bearing assemblies. Maximum halyard diameter is 5/16 in.