Helical gears are cylindrical disks which have involute shaped teeth cut into their face at an angle. KHK's stock helical gears are quiet, compact and economical. They are suitable wherever you require high-speed rotation including in machine tools, speed reducers and other industrial machinery. Our helical gears are offered in alloy steel and carbon steel, with many configurations of modules and numbers of teeth. All of the helical gears that we offer allow for secondary operations such as opening the bore, adding of keyways, adding of tapped holes, but only a few allow for the reduction of the hub diameter to be performed. Our offering also includes products which have already had some of these secondary operations completed. These products are identified by a "J" in their part number and they are available within 10 calendar days.