3-inch casters, Custer (certified), casters are provided by Shenzhen Logistics Equipment Co., Custer. Shenzhen Custer Logistics Equipment Co. (www.szcaster.com) is specialized in "casters, forklifts, aluminum ladders, aerial platform" of the enterprise, the company of "honesty, hard service" concept, to provide you with the most quality products and services. Welcome to inquire! Contact: Iso. The structure of a single caster wheel mounted on the bracket made, for mounting on equipment below allowed to move freely. Casters are divided into two categories: A fixed castors fixation with single-round 6-inch casters, can only move along a straight line. B Caster 360 degree turn of the bracket with single-wheel casters, can travel freely in any direction. (Here are the major considerations) how to select the appropriate wheel a select wheel material: first consider the use of road size casters, obstacles, using the residual material on the site (such as iron, oil), in which the environmental conditions (such as temperature, different conditions such as weight at room temperature or low temperature) and can carry a wheel to decide to choose the appropriate wheel material. For example: rubber wheel is not acid, oil and chemicals, super polyurethane wheels, high-strength polyurethane wheels, nylon wheels, steel wheels and high temperature wheel is able to be applied to different special environment.