HEIL SOUND Shock Mount For PR Series Microphones (PRSMB) The HEIL SOUND Shock Mount For PR Series Microphones is a flexible support system that helps suppress low-frequency rumble on the microphone line by absorbing and damping vibrations picked up from the studio desk or console. The PRSM is designed for use with the large-diameter professional-grade Heil Sound microphones including the PR 30 and PR 40. Its 5/8 threads mount onto the PL-2T Topless and other mounts for easy installation. The shock mount weighs 16.2 oz.