Currently on the market there are national standard aluminum profiles and European standard profiles

GB aluminum larger difference with the European standard aluminum that:

One. Groove different profiles at a fixed place different connection profiles slot nuts, national standard profile slots placed ordinary square nut, the European standard profiles to be placed on special shaped nut.

Two. Chamfered corners different profiles, GB profiles four corners chamfered small, basically a right angle; European standard profiles four corners of a larger arc chamfering