Soft and flexible o rings, simply snapping on This O Rings Assortment Set includes up to 200Pcs of 15 different sizes of o-rings The metric o rings leaks in fuels or water plumbing, machinery, hydraulic, and pneumatic connection; provide secure seals for any oil, air, and water seal application(faucet, sinks Stored in a organized resealable case saves you effort in tidying up and choosing sizes Make of Silicone and Rubber, great water and oil resistance, great good sealing, resistant, wear resistant, Manufacturer: REITINGE