product description FZH (copper-based), FZL (aluminum), FZP (resin base) to keep the ball solid, respectively, copper alloy, hard aluminum, POM resin matrix, and on its outer surface, processed orderly, appropriate size, shape special cavities, in its cavities inserts Rolling ball. Mouth using the latest circumferential groove ball lock technology, effective solution to the traditional lock ball and indentation style lock ball can not completely prevent the ball off problems. Hole bottom machined spigot 90 ° free rotation so that the ball in the hole without falling off. Because of a diameter greater than the wall thickness of the ball retainers, so when using the ball up to keep the circle, cylindrical surface, direct contact with the mating hole axis, the matrix (retainer) floating in the middle, and Matching the difference is less than the radius of the hole and shaft diameter steel balls, namely balls and match for the interference fit, with high accuracy, flexible shaft and bore relative motion. A retaining ring replacements.