ROVI Products is a leading manufacture of internal expanding collets to fit 5C, 3J and 16C spindles, capable of holding on bores ranging anywhere from .065" to 6" in diameter. Our system is composed of three parts: a hardened and ground sleeve to insure accuracy; a rod assembly which consists of the threaded pull rod, 5C collet nut, lock nut and expanding screw; and the machineable expanding collet. Unlike other designs, our expanding collets have a taper on the shank that locks into the sleeve creating a very rigid collet which in turn gives you better concentricity. All ROVI collets are machineable and completely consumable (.0005" TIR is easily held on production runs and holding .0002 TIR is not uncommon). ROVI collets save time, labor and cost because they can be remachined for many different jobs. When the collet has been consumed or needs to be replaced, simply remove existing collet from the sleeve and insert new collet. It is not necessary to purchase the sleeve and rod assembly for every new collet as other manufacturers may require.