This check valve is made of , which can withstand use. Features the PP material, which has high durability, not easy to deform. Fine workmanship, ensures practicality. Features -Color:Transparent -Material:PP -Size:3.80X1.50X1.50cm/1.49X0.59X0.59in Suitable hose: 4mm inner diameter Temperature resistance: 100 degree centigrade Opening pressure: 0.005MPA (0.05kg water pressure) Reverse back pressure: 0.7MPA (7kg water pressure) - Weak acid and weak alkali resistance, can resist up to 100 Celsius degree. - and gasoline resistance, can be used for gas and liquid . - Suitable for home, restaurant, hotel, supermarket, shopping mall, company, etc. - The professional and practical water connector will not leak easily, you can use it with confidence. - workmanship, reasonable structure, professional and practical, can bring you convenience. Package list: 6 valves