The Harcoster plastic garden tap is compatible with most hose connections for all butts, barrels and water tanks  having a 3/4" BSP thread, they are supplied with locking nut and two rubber washers, they are  ideal for water butts since the large bore results in a better flow of water.

 

A plastic tap can also be fitted to an oak barrel water butts using a ¾ inch tapered barrel tap adaptor.( see barrel tap adaptors )