No offense taken. I'm in Western Washington state. The home I previously lived in had fine machine threads on the exterior faucet. I assume this was to prevent

No offense taken. I'm in Western Washington state. The home I previously lived in had fine machine threads on the exterior faucet. I assume this was to prevent attachment of a hose without a vacuum breaker. Here's the item I had to purchase to attach a standard garden hose. https://www.amazon.com/dp/B002OU6ZSA/ref=cm_sw_r_cp_apa_tbA-BbHW6Y0AE https://www.amazon.com/dp/B002OU6ZSA/ref=cm_sw_r_cp_apa_tbA-... Now that I think about it though I believe you are correct about the diameter of the port being consistent. It is indoor plumbing valves that I've run into a variety of sizes of. 1/2" vs 3/8 compression.