The 51AAD-B24-A20L is a sealed 1/2" (12.5 mm) square potentiometer control manufactured by Bourns, featuring a linear cermet element with ±10% tolerance and a 10 kO resistance value. This single-section potentiometer is designed for PC board mounting with a 100° center terminal spacing and includes a metal bushing and shaft configuration, sealed for board washing to ensure reliability in harsh environments. The device is RoHS compliant and offers an effective electrical angle of 270° ±5°, with an absolute minimum resistance of 2 ohms maximum. It is commonly used in professional audio applications, instrumentation, and control systems where sealed, reliable potentiometer performance is required.