The clamping bores of GN 147 flanged connector clamps are not machined and specially designed for construction tubings GN 990 or DIN 2391, DIN 2395 and DIN 2462 respectively.
The square designs are also suitable for use in profile systems.
The standard version of the clamping screws are socket cap screws with hexagonal socket DIN 912. They can be replaced by clamping kits GN 911 (article code see table of dimensions).