Quantity per package: you will receive 2 radiator keys, ideal for replacing them, preventing the central heating system from breaking down during the winter months Measurement: the radiator key is approx. 3 x 2.2 cm or 1.18 x 0.866 inch, the inner square edge is 5 mm or 0.197 inch and the outer diameter is 8 mm or 0.315 inch, one size fits most radiators in the market, easy use and brings convenience to your life Strong material: these radiator wrenches are made of quality zinc alloy, light and practical, durable and sturdy, not easy to break, easy to hold and turn, even after screwing in a few rigid valves, there is no still no distortion on the key Utility design: lightweight and durable, radiator wrench can save effort, good tool for every home, they are very sturdy and not easy to break or deform Wide applications: the radiator key is useful for bleeding air from radiators