Material: acetal (black). Cross-pieces: brass. Joint faces are fitted with brass inserts, with 2 set screws per hub. Temperature range: -20°C to + 60°C. To shorten the teleshafts, please always cut off the same length on either side. * The stated peak torque refers to Lmin. (telescope retracted). The max. torque for extended telescope has to be determined empirically and subject to the respective application. ** Bore-reducing bushes see below. 1) Joint faces fitted with brass inserts with 2 set screws per hub. 2) Joints only fitted with metal inserts, without set screws.