Perko 1-1/4" Thru-Hull Fitting w/ Pipe Thread Bronze. Flange is machined to fit hull and grooved to retain bedding compound. Neck. is threaded to approximately 3/8 inch from flange.. Cast bronze.. Technical Information:. Pipe Size Inches: 1-1/4. Mouting Hole Diamete Inches: 1-5/8. Maximum Hull Thickness Inches: 2. O.D. Flange Inches: 2-3/4. Model Number: 0322DP7PLB. Ship Weight: 6.0/29.4 lbs.. MADE IN THE USA