you get it from industrial electrical wholesalers - the kind that deal with high voltage on a day to day basis. Cable identification is a serious business, and it costs plenty too. There are lots of special labels available, have a look see. Some strap on, some use 'cold shrink'. Cold shrink is a heavy duty version of heat shrink... it's a lot thicker (like, can be used as a handle on a hammer for example). The way it works is that it has a hard plastic spiral in the core, and an outer flexible sheath... maybe latex? You slip it over what you need to cover, then pull out the core... the outside shrinks down to its pre-stretched size. Heavy duty, but not cheap. Its transparent.
Other options are the little labelmakers that you can buy in stationary stores. Once you get one, you'll wonder how you ever did without it. They sure are cheap, and lots of tape options available - waterproof, hi vis yellow, metalic, paper etc... print out custom labels quick smart. You can tape over them with some clear tape, will last for a long time. I've used mine to label all the drawers on my toolboxes, shelves, all the toolboxes on my truck for what goes where etc. Makes it easy on new ground staff too because everything is clearly identified.
Shaun
