Crimp couplings must be installed by a fully trained assembler with appropriate machinery. Always confirm crimp ODs & tolerances. 1A Fittings are used on GH663, GH681, EC115, EC215, FC639, FC839B, FC849B, GH793, GH781, FC735, GH195, GH120, FC619/2661 & FC579 hoses. STC Connector Maximum Pressure Rating: # 04 - 6,000psi, # 06 - 5,000psi, # 08 - 4,250psi, # 10 thru #16 4,000psi