³⁄₃₂" dia. shanks are the jeweler's preferred standard for burs and small rotary tools. They fit the adjustable chucks found on most flexshaft handpieces as well as ³⁄₃₂" handpiece collets.

Hart (Bearing Cutter) Burs are used to cut seats in prongs, flush settings, & channels. They are available with 45°, 70° or 90° cutting angles. They can also be used for bright cutting.

High Speed Steel (HSS) burs strike a balance between cost and durability. They maintain their hardness (temper) better than vanadium steel and cost less than carbide steel.