I believe that the screw-in valve type shown in the photo below is called a "Boston Valve". It's used on many kites including Ozone and Naish etc...
I'm finding that the wider diameter cylindrical shape pump nozzle doesn't fit very tightly into the valve hole, so when the kite reaches 2 or 3 PSI, the pump nozzle pops out due to not being a tight enough fit. So then I have to pump the remainder using 1 hand to hold the nozzle, and one hand on the pump
Has anyone else experienced this problem, and have a solution?