The adaptors are available with either ½” BSP or ¾” BSP connections. A ½” BSP tap will generally give an adequate flow of water but those that require a higher flow rate may wish to fit a ¾” tap. They are also available in a range of diameters to suit different hole sizes. This makes them ideal for replacing a wooden tap in an oak barrel with a brass tap for example, since it is possible to re-use a hole drilled for a wooden tap by selecting an adaptor to fit that hole. These adaptors are designed for fitting standard BSP threaded plastic or metal taps to wooden barrels. The adaptor is tapered with a spiral thread on the outside to assist fitting and sealing to the barrel. They are fitted by simply screwing the adaptor directly into a suitably sized hole. Glue or sealant is not required.