I highly suggest that you dont purchase it at frozencpu. Buy it at snt-systems. Innovatek did a ripoff of aqua computer's reservoir. You will have to buy the barbs elsewhere, and the fitting extension is not necessary. Any 1/2 barb will fit into the screw. Goto snt-systems and buy it there, it will cost you the same amount as buying the innovatek after you buy the barbs for that. SNT gives you the barbs and mounting as well, frozencpu doestn come with the mounting. But to answer your question, yes, its 1/2 and 3/8 compatible.