A - Self tapping screws.
For fastening to pre-drilled sheets and purlins.
B - Stitching screws.
For overlapping profiled sheets.
C - Light section screws.
For drilling through single skin to cold rolled purlins.
D - Heavy section screws.
For drilling through hot rolled purlins.
E - Sheet to timber screws.
For fastening sheet metal to timber.
F - High thread screws.
For fastening composite panels to steel rails and purlins.