Interstate Pneumatics F7326-50 Brass Fitting Hose Ferrule 0.593 inch Inner Diameter x 1.0 inch for 3/8 inch hose 500 psi Pack of 50 0.593 Inch Inner Diameter x 1.0 Inch Ferrules 50 per pack Wall Thickness = 0.5 mm Material: C46500 Brass for 3/8 inch hose, 500 psi