The DEWALT® 4 In. 18 TPI straight back bi-metal reciprocating blade (5 pack) improves on your existing tools so you can work faster and get better results on the job. The blade is designed for cutting threaded rod, angle iron, conduit, and more. DEWALT® understands that you can't afford to waste a minute on important jobs, so a specially formulated anti-stick coating minimizes friction and gum-up for smooth cuts every time. With a patented tooth design that utilizes sharper tooth geometry and an aggressive shank angle, the blade has increased tooth contact so the fast cut rate will be maintained as the blade wears.