Clock Type Vent Key Brass Wing design to allow force For hard to open vents Ideal for central heating radiators Easi Plumb Clock Type Radiator Vent Key | EpbvkThe Easi Heat Brass Clock Radiator Vent Key has been specifically designed for venting central heating radiators. The key features a wing design that offers the possibility to exert force which is sometimes necessary to a open a vent that has been closed for a long time. The Brass Clock Radiator Key may be easily attached to your key ring so you always have it close to hand when needed.