Have a quantity of 10 75/3500 tubes for sale. Tubes have 3 grooves total. 2 internal and 1 external. These are 6061 T6 drawn tubing and cut and grooved to Gorilla specs. These tubes are not anodized. Please email Gary at [email protected] if interested. Paypal and shipping not included. Included zip to calculate shipping charge. Paypal and shipping charged are no additional funds for me. What they charge is what you pay. thanks Gary