a damper for use in submerged hydrophone suspension systems including an elongated mass cylinder defined by a tube of flexible synthetic plastic film utilizing a check valve located at each end permitting water to enter the tube and preventing egress . additionally , each tube end is provided with a disk transversely disposed to the tube length and of a diameter substantially greater than that of the tube to provide drag and hydrodynamic mass damping . the tube and disk are of a configuration to eliminate vortex shedding and the entire damper assembly is capable of being folded and packed within a concise configuration prior to deployment .