Polyclutch® Jaw Type Clutches permit extremely simple, reliable phase adjustment, and/or engage-release between a shaft and gear, pulley, roller, etc. The D Series is knob operated, the J Series is lever operated. Clutch teeth are precision machined from solid steel blanks, 3º tooth spacing (120 teeth) is standard. Alternate spacings available. All Polyclutch jaw clutches are stronger than the shaft driving it.