Countersunk head screw made of steel, strong and durable, and will not rust even in humid environments High strength, fully threaded, thick and sharp. the screw head is not easy to break This countersunk screw is self-tapping with shaft and coarse thread, so there is no need to drill holes in advance Not easy to slide, smooth inside and outside without burrs, deep thread design provides good fixing force Can be used in various fields, such as furniture making, house maintenance, ship parts maintenance, mechanical reinforcement, etc.