The first one I bought was a 12fr 5cc bulb. Next three were 14fr 5cc bulb, then tried a 16fr 5cc. I felt that was getting a little big. You can order catheters online but most places require prescriptions, so you'll need to check the requirements before you buy. I think southwest medical carries them. I've never ordered from there so I can't vouch for them. If you've never read a cath procedure you might want to brush up on it, and always make sure to be clean. I never had any complications from them. Just make sure you're careful!