Great food grade quick disconnects. They are made of Polysulfone plastic, which is food grade up to 280F and can handle up to 125 psi. This set has 1/2" Male NPT on the male connector and a 1/2" Barb fitting on the Female connector. The o-ring used is EPDM and the springs are 316 stainless. Perfect QD set to use to set up one handed operation tubing from a 1/2" FPT threaded fitting to another 1/2" FPT threaded fitting. Two sets would be required for each line of tubing.