Easy to cut, Universal 6″ NEOPRENE RUBBER (not hard plastic) coupling. You get 1 each; 6″ sleeve, 5/16″, 7/16″ & 1/2″ ends, bubble packed. Quiet running. No worry about sizing as this covers almost all residential burners new and old. Proven design and materials. «D» Drive ends, no set screws. If you are replacing the pump it is a good idea to renew the coupling. SHIPS FAST!! We have many other parts. If you don’t see your item here, contact us with your request. We will let you know if it is available.