JZP-4.2-SC Rubber Shock Absorber: Low Total Cost of Ownership and Multiaxial Shear-Compression Isolation Quick answer: The JZP-4.2-SC is a friction-damping rubber shock absorber (vibration isolator) with a nominal load of 4.2 kg, a damping ratio of at least 0.5, and a load path that handles both shear and compression. Its solid-phase design needs no air supply or power, which keeps lifetime ownership costs low. What Is the JZP-4.2-SC? The JZP-4.2-SC belongs to the JZP family