Illustrate:The advantage of this connector is that the profile does not should be tapped or punched, and the installation is firm. It is more suitable for profiles with arcs, equivalent to 6630R or 8840. Suggestion:40 collection can solely be used for the European standard forty sequence profiles with a wall thickness of 2.0 or more. If the wall is comparatively thin, the exterior thread of the threaded sleeve cannot be locked and cannot be fixed. Material: galvanized Recommended screws: For 20, it is suggested to apply hexagon socket M4*30 screws For 30, it is suggested to apply hexagon socket M5*35 screws For 40, it is suggested to use cylindrical head hexagon socket M6*40 screws For 45, it's endorsed to use hexagon socket M6*40 screws NOTE:Avoid that the screw head is too extensive to fit into the slot.