Good Quality: These radiator keys are made of quality zinc alloy, strong and sturdy, not easy to break, easy to hold and turn. Application： The radiator valve keys are mainly used on faucets and radiators, 5mm radiator keys can be used as drive wrenches for the same size.Keys are designed for the bleeding of domestic radiators - Has a square opening.great for replacing, avoiding the central heating system breaking down during the winter months.Suitable for many radiators on the market. Size ：The thickened radiator valve key has 5 x 5mm/0.2 x 0.2 inch square hole,The extended radiator valve key has 5 x 5mm/0.2 x 0.2 inch square hole，Two lengths to meet your different needs. LOWER ENERGY BILLS: When your radiator is working properly, it can heat your home more efficiently, which can help reduce your energy bills. Easy to Use & Portable：Simply place the universal square key on the radiator valve (the air valve on the side of the radiator) and turn it carefully. For safety, place a water container underneath.Every radiator lock key feature 2 pre-drilled hole for convenient carrying and storage, not easy to get lost.Color: B Manufacturer: ChaneeHann Model Number: 5789 Part Number: 5789Features - Material: Zinc alloy. - Color: Silver. - Every radiator lock key features pre- drilled hole for convenient carrying and storage, not easy to get lost. - Our radiator valves keys are mainly used on faucets and radiators, and can be used as wrenches for different kinds of valves. - The product is light, portable, not easy to, easy to use, and is a convenient and practical radiator exhaust valves. - Fits many radiators in the market, easy to use and brings convenience to your life. - Light and durable, the radiator wrench can save effort, good tool for every home, they are very sturdy an