For ease of use and all-round performance, these Screw-Tite wood screws take some beating. They're designed with an innovative Tri-Lock shank and thread - this cleverly combines the benefits of a single and twin thread on the same screw. With 25% less insertion torque, you'll get a fast insertion that eases the strain on your power tool and helps to extend battery life. It won't damage the timber, and ensures a strong and secure fixing - once you've driven it in, the Screw-Tite stays in! Perfect for use in timbers, boards, hard and softwood. Can also be used for sheet steel, plastic, masonry (pilot hole required) and more. Tri-Lock shank - 25% less insertion torque and no timber damage. Fast insertion places less strain on your power tool's battery. Firm and secure fit - once driven in, it stays in. Excellent close-to-edge driving performance. Screw-Tite Pozi Countersunk Screw 4 x 70mm (100 Pack) in Gold Plastic. Tri-lock TS thread provides a single and twin thread on one screw with a quick, balanced start teamed with a high pull-out retention. With the strength of a high tensile bolt, the screw will not snap and works in almost any material without the need to pilot. Tri-lock shank allows the screws to go in easily, locking into the material and ensuring once it's in, it stays in! Underhead ribs ream and self-countersink for a clean, flush finish.