Features: 1.Nitrile Rubber: Adopt NBR (nitrile butadiene rubber), static and oil resistant, UV resistant, heat resistant, wear resistant, long service life 2.Application: O rings are widely used for automobiles, faucets, hydraulic pneumatics, seals, industrial equipment, electrical appliances, etc. 3.Simple Operation: This O ring seals kit is easy to install, expandable, easy to use, and can be used for maintenance 4.Convenient Storage: The transparent plastic box has 18 interlayers, arranged according to the purpose, and the size chart is attached to facilitate the differentiation of different sizes 5.Sufficient Quantity: There are 225Pcs and in 18 popular sizes O ring seals kit , which can meet your needs, and durable Specification Item Type: NBR O Ring Assortment Model: HX086005 Material: NBR (Nitrile Butadiene Rubber) Parameter:  Size(Approx.) Quantity (Pcs)  3x1mm / 0.12x0.04in 20 4x1mm / 0.16x0.04in 20 4.5x2mm / 0.18x0.08in 20 5x2mm / 0.20x0.08in 20 6x2mm / 0.24x0.08in 20 6x2.5mm / 0.24x0.10in 20 13x3mm / 0.51x0.12in 5 14x2.5mm / 0.55x0.10in 5 17x2.5mm / 0.67x0.10in 5 18.4mm / 0.72in 5 20x2mm / 0.80x0.08in 5 22x2mm / 0.87x0.08in 5 6x3mm / 0.24x0.12in 20 7x2mm / 0.27x0.08in 20 8x2mm / 0.31x0.08in 20 9x2mm / 0.35x0.08in 5 10x2mm / 0.40x0.08in 5 12x3mm / 0.47x0.12in 5 Package List 225 x O Ring1 x Storage Box