A detent anvil retains the socket with a spring-loaded ball like on ratchets. A hog ring anvil retains the socket with a steel ring in a groove on the square drive, as on most air impact wrenches. The hog ring anvil tends to be more ornery to fit sockets onto and off from, but also retains them better.Click to see full answer. Just so, what is a hog ring?A hog ring (also known as a friction ring) uses a circular ring around the square end of the driver to hold the socket in place. A detent pin uses a spring loaded ball bearing on one side of the square end of the driver to hold the socket in place.One may also ask, what is a friction ring? Friction ring: Rubber ring keeps the socket on the square. Easier to remove the socket. Hence, it’s used for most purposes where more than one socket is needed. In this regard, what is a detent pin on an impact wrench? Detent pin means you need a nail or punch to change the socket. If you’re a steel erector and you dont want your socket falling out, get the detent pin model.What’s the difference between Dewalt dcf899b and dcf899hb?As can clearly seem, the main difference between a Dewalt Impact Wrench DCF899B vs DCF899HB lies in the anvil. While the DCF899B comes with a Detent Anvil, the DCF899HB comes with a Hog Ring Anvil. An anvil is the part of the impact wrench that receives the impact.