Taper (or Roughing Taps) are used for starting precision and difficult holes. This tap has a lead of eight threads, but no size reduction. Recoil taps are manufactured to precise standards from either High Speed Steel (HSS) with ground threads. They have a larger diameter but the same pitch as a standard tap in order to accommodate the wire insert. The Recoil thread insert when installed into a correctly tapped hole will provide the applicable internal thread tolerance for the installed bolt.