Specially designed for attaching tongue and groove floorboards and panelling. Provides a secure hidden fixture without causing damage, allowing a flush fit with the next board. Reduced head for concealed countersinking.Plain shank for pulling the two substrates together without manual clamping.Coated with a high-molecular polymer lubricant that reduces the insertion torque by up to 52% and increases rust protection up to 20 times longer than a standard zinc plating.Dual angle thread gives an ultimate performance and an exceptionally high pull-out resistance.Patented twin cut technology for rapid “pick-up” and reduces timber splitting.