Dual potentiometer type S2091-8 was made by CTS for Aircraft & Commercial Enterprises. If you look this Part# CTS S2091-8 up on the Web it is a part for Cessna Aircrafts. It is 1K Ohm linear taper for both potentiometer selections. It has 2 independent shafts so it can be used with a dual knob (not included). It panel mounts by way of hardware included. Bushing is standard 3/8" dia. threaded. This is a very high quality, well made potentiometer in sealed Aircraft & Commercial Enterprises bag. New - Retails for $19 and higher.