Get durable flat rings in Pune from Puja Seals – ideal for leak prevention and load distribution in various sealing and industrial application , Functional but straightforward sealing devices are flat rings (or rubber flat rings) and flat washers. They are usually made of rubber sheets and are compressible between a mating surface to form a seal. Their flat shape would match a stationary application, in which they are employed to obtain a basic, durable seal to leak fluids or gases, or to attenuate vibrations and insulate.