B1 (together with B2) is used to join the Cable Trays. B1 has two extra holes, diameter 10 mm (0.39 in) and 6.5 mm (0.25 in) that can be used for connection to ground. The Fitting can also be used to mount the tray to wall, ceiling and floor. Or to mount lighting fittings directly on the tray.
Delivered without bolt and nut (M6).