The Mallory MR22 Universal Flatted Shaft Volume Control is a replacement potentiometer component manufactured by P.R. Mallory & Co. for vintage electronic repair and radio restoration. Designed with a broad base measuring 1-1/8 inches in full diameter and a 3-3/8 inch shaft length, this control features a shaft configuration with a 3/4 inch round outer diameter and a 1/4 inch inner flat diameter for precise knob fitment and reliable resistance performance.