Unique with Helical gears are crossed helical gears which are also called Screw gears. These gears have helix angles of 45 degrees. As such, they are the only helical gear pairing that can be used in either a left hand - left hand combination or a left hand - right hand combination. When used in a left hand - left hand combination the gears operate with non-parallel and non-intersecting axes. In this fashion they operate in a similar manner to miter or bevel gears. When used in a left hand - right hand combination, they act like traditional helical gear pairs. Our Screw gears are offered in many materials, modules and numbers of teeth. All of the screw gears that we offer allow for secondary operations such as opening the bore, adding of keyways, adding of tapped holes, and 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.