Recirculating units support high-precision and are rigid and compact units with unlimited travel. They are used as standard with linear guideways of type R or RD. Types SK and SKD ball recirculating units (with damping elements from size 6) are suitable for small to medium loads. For medium to high loads, the right choice is the type SR recirculating unitwith cross rollers. The SKC recirculating unit wasdeveloped for minimal lubrication, vacuum, and clean room applications. It has ceramic balls combined with TEFLON® balls to further minimize abrasion.