The SMC DOT Straight Cartridge is a push to connect replacement unit. If the PTC ports on your Air Lift or AccuAir manifold happen to be leaking (and the air line going into them is cut at a perfect 90° angle), the o-ring inside of the port has most likely been damaged and will need to be replaced.
3/8" PTC Press In Manifold Fitting | SMCKV2H11-Q11
⚠️CALIFORNIA WARNING: Cancer and Reproductive Harm - www.P65Warnings.ca.gov