Portagas is revolutionizing the calibration gas industry with our new Portagreen™ "Strip and Ship" recyclable cylinder program. Eliminate the hassle associated with disposing of your empty cylinders. We provide you with an easy option to reduce your waste and carbon footprint. Each cylinder comes with a prepaid return-shipping label. Once the cylinder is empty, strip off the shrink-wrap to reveal the return label and hand it off to your shipper. Now it's out of sight/site, out of mind. Easy and convenient. Just "strip and ship". Step 1. Once the cylinder is empty, it is no longer hazardous. Simply follow the return instructions printed on the cylinder. Step 2. Remove shrink-wrap containing the outbound shipping labels. Step 3. Place the empty cylinder into the original shipping container and hand it off to FedEx.