Features: 1Red Line Indicator: A red line indicator warns the user of any vacuum loss. When the red line appears when you lift the suction cup, just pump the plunger with your thumb, no need to lift the cup off the exterior. 2Strong Suction Cup: This suction cup has a lifting load range of 130 to 520lb for quick attachment on flat, non porous surfaces. 3Convenient to Use: This is a very handy vacuum suction cup, and the check valve allows repumping without losing the remaining vacuum. 4Rubber Material: Durable, odorless, strong rubber suction pads and ergonomic handle, work in low temperature and hold vacuum for 6 hours. 5Wide Application: Suction cups are ideal for lifting and moving materials such as glass, tiles, aquariums, plastics, engine valves, furniture, metal, slate and appliances. Item Type: Glass Suction Cup Material: Rubber Suction: Approx. 150kg/ 330.7lb Diameter: Approx. 20.3cm / 8in Package Included: 1 x Glass Suction Cup 1 x Cotton Filter 1 x Sealing Ring 1 x Storage Box