M10x110 Galvanised Cuphead Bolt (or Coach Bolt) is a heavy-duty fastener with a round, domed head, a smooth shank, and a square section underneath that bites into timber, locking it in place as you tighten the nut, making it ideal for connecting timber to timber (like in decking, pergola's or fencing) or timber to steel, with the galvanised coating providing excellent corrosion resistance for outdoor use. The "M10" signifies a 10mm diameter, "110mm" is its length, and "Galvanised" means it's coated in zinc for protection against rust.