These ball lock posts include a 1/4 inch BSP thread so you can attach it to a wide range of other fittings. The posts include a 20mm long thread, an o-ring, poppet, locking nut and short dip tube. Longer dip tubes can be purchase separately (part#KL03124). This would enable you to make a keg out of any pressure vessel if you wanted to. The assembly can also be fitted to our MKIII and MKIV regulators, gas manifolds, Bottle Filler Beer Guns (very useful)  and various other items.
We would highly recommend attaching one of these to your regulators if you use the CO2 Cylinder bracket. It makes it much easier to detach your CO2 bottle without having to pull the Kegerator out.