Contain 18 sizes， size included (Inside Diameter x Diameter):<br /><br />12 x 2mm (20 Pcs)<br />11 x 2mm (20 Pcs)<br />8 x 2mm  (20 Pcs)<br />4.8 x 1.5mm (20 Pcs)<br />7.8 x 1.9mm (20 Pcs)<br /> 9.25 x 1.78mm (20 Pcs)<br />12.42 x 1.78mm (20 Pcs)<br />6.8 x 1.9mm (15Pcs)<br />8.8 x 1.9mm (15Pcs)<br />9.8 x 1.9mm (15Pcs)<br />10 x 2mm (10Pcs)<br />10.82 x 1.78mm (10Pcs)<br />10.77 x 2.62mm (10Pcs)<br />15.54 x 2.62mm (10Pcs)<br />13.8 x 1.9mm (10Pcs)<br />17.17 x 1.78mm (10Pcs)<br />20.22 x 3.53mm (10Pcs)<br />10.69 x 3.53mm (10Pcs)<br />Descriptions:<br /><br />Assortment O-Rings with convenient resealable plastic case.<br />Total 8 most popular used O-ring sizes.<br />Hydrogenated Nitrile Butadiene Rubber (HNBR)， also known as Highly Saturated Nitrile (HSN) is special class of nitrile rubber (NBR) and is for mission critical applications.<br />HNBR can be formulated to meet application temperatures ranging between -45 degrees C and 165 degrees C， and HNBR is classified by ASTM as DH-type polymer.<br />The HNBE O Ring can be bear the impact， bear the freon(F12， R123a)， bear the oil， and watertightness， defendtheultravioletray， bear the corrosion.<br /><br />Packing list：<br />265 Pcs±2% x Air Conditioning O Ring<br /><img src="http://img6.eachbuyer.com/x9/p100/eb01373_1.jpg" />                                                        <img src="http://img6.eachbuyer.com/x9/p100/eb01373_2.jpg" />                                                        <img src="http://img6.eachbuyer.com/x9/p100/eb01373_3.jpg" />                                                        <img src="http://img6.eachbuyer.com/x9/p100/eb01374_2.jpg" />                                                        <img src="http://img6.eachbuyer.com/x9/p100/eb01374_3.jpg" />                                                        <img src="http://img6.eachbuyer.com/x9/p100/eb01374_4.jpg" />