This mandrel can be installed on the Ruger Moon Clip Loading Tool (#18751) to simplify loading and unloading of rounds in the moon clip. It is made of aluminum and is .595” in diameter. This mandrel is designed for use with TK™ Custom Moon Clips (#18734) and Ruger Moon Clips (#90634) for the Ruger Redhawk, .357 Magnum, 8-round. Made in the USA by TK™ Custom.