Rotary Joint XC The FlexLink Rotary Joint XC allows two XC structural beams to be attached to each other, allowing one of the beams to swing. The joint is intended for use in pairs, to avoid movement loads. The joint should be fastened into the T-slot of each beam with 2 slot nuts (RS stock-no. 248-9859) and M8x14 DIN7984 socket head screws (note: M8x14 DIN 7984 screws are not supplied and not currently available separately from RS). The maximum load for a pair of joints is 1000N.