NKRI Offers Hi-Quality O-Ring Service Kit No. NKRI-111 is consisting of 382 pcs of O-rings of 30 different metric sizes, contained in an acrylic/plastic box having an attractive appearance. It is made from High Nitrile (NBR) Rubber in Black colour having Shore Hardness: ‘A’ 70, withstanding Temperature -40oC to +120oC, which is excellent resistance to wide range of fluids, including mineral oils, hydraulic and lubricating oils, greases, fuels, water, steam and many other fluids. NKRI products have an excellent reputation for quality, reliability and performance against exacting technical specification.