Hello, my system came with these and I've since upgraded to all cam-locks. These work fine, and were used on 3 sets of hoses, as well as in/out of a chiller. I believe they are 1/2" since that is what the male end of the fitting is. The threads are 1/2" NPT. The barb is 1/2". $25 shipped priority USPS CONUS. They can be picked up in Central Jersey if you want. Paypal or check, etc.