The 1/4" Stereo 3 Conductor thick panel mount jack without cable clamp, Black satin chrome finish,1/4 inch end pin jacks feature long threaded bushings ideal for mounting into panels and chassis up to 1.25 inches thick. The metal bushing helps eliminate hum pick-up, and is ideal for musical instrument and speaker connections. Jacks mate with standard 1/4" phone plugs and mount in a single .469 inch diameter hole.