Dimensions for Close Tolerance Tapped Bosses with Unified Threads for Pipe Coupling Union Adaptors using Pipe Fitting 'O' Ring Seals, eg. AS43003. (Recommended for use with pressures above2500 lbf/in2. For pressures up to 2500 lbf/in2, AGS 3911 recommended)
Data Sheet by SAE ITC TSC Aerospace Standards (Formerly ADS Group Limited), 07/01/1974