Milton H-Style Coupler 3/8" Male NPT Kwick Change Coupler S-1836Milton H Style Coupler 3 8" Male NPT S 1836 The Milton 3 8" male NPT H Style coupler is great for any workshop or garage. Milton's H Style couplers have a maximum pressure of 300 PSI, allow 67 SCFM of airflow, and are made right here in the U. S. A. Please see below for more features and specifications. Features and Specifications Milton H Style Coupler Maximum Inlet Pressure of 300 PSI Air Flow of 67 CFM 3 8" Basic Flow Size 3 8" Male NPT (Measures 5