It is Expensive and Time-Consuming to have your Tank Cleaned for use with NITROX. Once Normal-Air is Mistakenly-Used with it, you must for Safety-Reasons have it Cleaned-and-Serviced, don't let this happen to your NITROX Dedicated Equipment. Have NITROX Tank Sticker installed on all your cylinders used exclusively for NITROX Diving and there will not be a Costly-Mistake made. XS Scuba's NITROX Cylinder Sticker is Built-to-Last made from Durable Vinyl with Easy-to-Read Layout in NITROX Green and Yellow Colors. This 17" x 1.5" (43.2cm x 3.8cm) Sticker will not Peel-Off in Water with use and is designed for Cylinders with 4.13" to 5.4" (10.5cm to 13.7cm) Diameters.