Head:
Material:
Recess:
Fastenmaster Timberlok, Ledgerlok and Headlok screws just zip right in.
All are extremely strong, corrosion resistant.
Timberlok has become de-facto fastener for joining railway sleepers.
Ledgerloks are super strong, ideal for structural joints.
Headloks are THE fastener for ply faced insulation panels in flat roofing applications.