Made from aluminium alloy with hardened steel running tracks. The balls are made from steel whilst the remainder of the carriage is made from polyamid.
A type rail is bolted from the TOP with the cap of the bolt countersunk into the rail. B type rail is bolted from the BOTTOM (with the cap of the bolt located in the structure to which the rail is bolted). The rail is made from aluminium with a hardened steel running track.
