Features and Benefits:�Grease fitting for the lubrication of mechanical systems�Trivalent zinc plating for resistance to corrosion�1/8" male PTF dry seal connection�Ball check valve for excluding contaminants�Maximum operating pressure of 10,000 psi"ALEMITE" PTF FITTINGS7/16" hex size.1-1/4" length.25/32" Shank length.Dirt-excluding ball check. Maximum Pressure: 8,000 psi. Exceeds 48-hour salt-spray test. 1958 has specialty cap providing a second seal for dust-proof applications. Used on many industrial machines and heavy equipment.