Is the opening for the supply line on the shutoff valve a standard size? Also, if I use the faucets I bought that has the 1/2" interior diam. copper connector soldered on, what size is that in plumbing language? I'm reluctant to take both the old and new faucets to the store to match things up. Thanks again.

Sorry... missed your last post somehow!

Most shut off valves that feed faucets have a 1/2" copper tube supply (also called 5/8" O.D.) with a 3/8" O.D. compression thread for the braided hose supply which, of interest, usually is a 3/8" O.D. compression x 1/2" IPS thread to connect directly to the threads of the faucet!