The 91A1A-B28-A22L is a Model 91 single-turn panel control potentiometer manufactured by Bourns, featuring a 5/8" square format with in-line PC pin connections. This device is available with either conductive plastic or cermet resistive elements, supporting resistance ranges from 100 ohms to 1 megohm depending on element type and taper configuration. The potentiometer features a shaft type "J" with a 6.00 mm diameter and standard lengths of 16.0 mm or 22.0 mm, utilizing bushing R for mounting. It offers virtually infinite electrical circuit isolation with metal or plastic shaft options and is RoHS compliant. The device is commonly used in audio equipment, instrumentation, and control applications where reliable single-turn adjustment and compact panel mounting are required.