Hello David, Thank you for your inquiry! The XS Scuba X Series High Pressure Twin Scuba Cylinder Package - 300 DIN Valve is a complete package. You’ll only need to make sure your BCD is set up to handle doubles. Most BCD HARD backpacks have indentations as to where to drill out the holes for the 2 bolts, allowing the twin tank bands to be secured to the BCD. If you have a soft back BCD, most manufactures have steel, stainless steel or aluminum back plates that can be integrated into the BCD.
http://www.scuba.com/scuba-gear-89/043223/XS-Scuba-X-Series-High-Pressure-Twin-Scuba-Cylinder-Package---300-DIN-Valve.html If you would like to place an order or have questions about our products, please contact one of our certified Dive Instructors at SCUBA.com by calling 800-247-2822 <> 949-221-9300 or e-mail us at: info@scuba.com
FULL MANUFACTURER’S WARRANTY 
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