Dive Signs Reusable Gas Analysis Stickers.
Write your analysis data on the sticker with a permanent marker pen then wipe clean with alcohol based hand sanitizer and a cloth each time you refill the cylinders.
Very effective and easy to read. Like all our other products, these are protected by very high endurance laminate so should last for years.
The Gas Analysis Stickers should be mounted on the flat side of your cylinder where they can be easily written on and read.