The Hultafors SRP 18W Snap-Off Knife is made of durable PC-plastic (polycarbonate) with a steel core for added stability. It is tapered for better visibility, access and control. It also has an ergonomic, rubberised grip and a 1mm thick metal blade rail for additional stability. Suitable for all-round use such as cutting plasterboard, insulation, aqua panel and wood. It comes with 4 blades, 1 in the blade rail and the extra 3 in the dispenser that the knife holds.