Type 17 Polycarbonate Roofing Assemblies 12 gauge-11 threads per inch x 50mm long screw class 4 coating
Type 17 Polycarbonate Roofing Assembly screws are for fastening the crest of polycarbonate profiles to timber.
Type 17 screws are a self drilling point for fastening into timber. The hardened point will also drill through thin metals up to 0.75mm thick that makes this point suitable for fastening sheets to timber battens. The screw threads extend down the point thus the screw "pulls" itself into the timber that reduces the required drilling pressure and reduces the risk of stripping of threads due to "over running".
The Class 4 corrosion protection system meets the requirements of ISO 9223 Category 4 (Outdoor application for moderate and severe environments).
AS 3566.2 (Self drilling screws for the building & construction industries) specifies the corrosion protection systems required on screw fasteners Classes 1, 2, 3 & 4 where Class 1 is intended for indoor application and Class 4 for environments up to and including ISO 9223 Category 4 (Severe industrial and severe marine environments).