JZP-4.5B Rubber Shock Absorber - Dual Vibration Isolation with Hermetic Sealing and Acoustic Suppression The JZP-4.5B is an assembled vibration isolator from the JZP-B series of Xi'an Hoan Microwave Co., Ltd. It pairs an alloy steel spring with a vulcanized rubber cushion: the spring absorbs low-frequency displacement and shock, while the rubber element dampens higher-frequency micro-vibration and dissipates it as heat. The result is a compact mount that keeps pumps,