The Twin module gives you an assistance in various activities with a bar, handles or pulleys. Contact support@macu4.com to select the module with the recommended spacer length (bridging the length difference between both arm) - we assist you in the assessment of the L4 and L5 values. Configure the module here with a M12 x 1.5 (metric) or a 1/2″-20 UNF-thread (inch) and choose the color combination that you like most. See the instructions for use in English, in French, in Italien or in Dutch.