here are mine i have two paasche H's and a noname brand from Princess auto
Paasche are single action the Princess Auto double action

the single action is a far better design in my oppinion as you can adjust the cone for the amount of paint you want to come out and you have a few different tips you can switch with
the double action has a fine needle you have to worry about bending the trigger usually wears out as you have to always pull back for the amount of paint you want to come out so the needle and trigger are always moving back and forth causing wear on both i had my one Paashe H for over 20 years

i got a double action Paasche. it has VL52124 down one side

These are mine, Paasche VL, and a Master's gravity feed. I got the second as part of a kit and it seems to be rather cheap and doesn't do a great job. Its the one I posted about on the "Airbrush problems" thread. I also have a Paasche H coming to test out some single action...action!