Pull ups

Just wondering I wear a pull up during the day for leakage. I can regulate the flow some what. But it depends how I am sitting or positioned in my pull up. Often I will leak, and I have to quickly re position myself. This can be a problem if I am driving. Which is a lot. Is there a pull up that doesn't leak? Or something else to use? The pull up is a great idea. but needs re tuning. adjustable so you can change on the go, or snaps for easy on and off. I tried the adjustable underwear but they really leak bad. I won't make that mistake again.