Ok, this will really get your goat. Just go to alibaba.com, check festo, smc, pneumatic connectors. You will get to the MANUFACTURERS of these things. THEY SELL FOR PENNIES EACH FROM THE MANUFACTURER AND NOT DOLLARS!!! Sure, you have minimums, but if you use a lot of them for air or fuel, then it doesn't matter. If not, then get a group order together. One thing you want to make sure of is that the connectors have the four little barbs in the compression tube that will grab and keep your tubing secured. Shipping is nothing and can be here in a few days. Even with shipping, the piece might only cost fifty cents, that and a few days beats the hell out of buy it now for $2-10 for one piece!!!! Oh, they will hold the air pressure, I have one tank in my MIBO A-10, pump it to 150psi, and I get 15 or more gear cycles out of it before the gear slows down. Good luck!!!