PETainer keg adapter

I have noticed a large amount of 30L PETainer kegs being used by bars to serve beer. A lot of these places just dump the kegs when they are done or give them away for free. I figured I could use these to brew my own beer and not have to pay for lots of glass carboys or brewing buckets. This adapter needs to be sealed with silicone sealant around the neck of the petainer keg and where the two halves join if you want this to be airtight. The adapter is topped with a standard mason jar thread so you can use a mason jar screw lid and flat top to adapt this container to any other fittings such as a airlock or a pressure relief valve (bear in mind the petainers have a max working pressure of 2.5 bar) I have included a couple variants for your testing pleasure, I have not had the chance to test print the variant with the built in pins or the separate pins yet but if i find any problems i will update. Minimal supports should be needed due to the semi circular shape.