Every time I find myself needing this information, searches turn up wrong or incomplete information. What are the standard sizes for automotive air conditioning service valve and hose fittings for different refrigerants, and how are they labeled for the sake of buying matching adapters, hoses, manifolds, vacuum pumps, etc.?
I'm most familiar with R12 where the sizes are 7/16" (low pressure) and 3/8" (high pressure), but I've also seen the "standard manifold hose" sizes described as 1/4" and 3/16". Is this just a difference in what's being measured (thread diameter vs hose diameter?) or is something else going on?
Ideal answer would be a table of each type of connection point (low/high pressure side, type of system or device(s) it's used with, etc.), what name(s) it goes by, and the physical dimensions the name is referring to.