Timco's heavy section self-drilling screws are designed for heavy section 12mm steel, with a fine self-tapping metric thread. They are plated with Silver Ruspert which is a reliable coating able to withstand over 1000 hours of salt spray testing. Specifically designed and manufactured to meet all the recognised industry standards and performance criteria. Hex head with a self-drilling tip Silver Ruspert plated for a durable corrosion resistant coating which can withstand over 1000 hours of salt-spray testing Designed for heavy sectional work Self-drilling screws for heavy section 12mm steel, with a fine self-tapping metric thread. Size - 5.5 x 100mm (16mm Washer) Quantity - 100