http://images.search.yahoo.com/image...sigb=133rg4ppa

you'll find out of you have one fail on you...I used to use them on most of my planes, had one fail and got rid of them.... You lose tank pressure, and it throws of your engine, and it will also spew fuel out of it. I still have one in use BTW, only because the guy i purchased the plane from had one on it, and dont feel the model is worth the fuss.