I have a Classic Accessories type valve on my pontoon boat and I bought a K-chek gauge to check the pressure with. it stated it fit the type of valve they use(can't remember the name). Anyway, I can't seem to make it work. What type of gauge do any of y'all use that have a Classic Accessory pontoon boat? Your help is appreciated. Right now, I am just going by the fact that they seem pretty inflated and that I can press in about 1/4" on them.