The Shrinking Toolholders are manufactured with an inside diameter slightly smaller than the shank diameter of the cutting tool. A heat induction unit is used to quickly heat the holder end of the Shrinker, expanding this inside diameter. At this point, the tool shank slips easily into the holder. The toolholders typically have a high level of interference. If the interference were small, the tool might simply be pressed into the hole a press fit holder. Shrinking Toolholders are very efficient and made for commercial use.