Those things are regulated in the US and they're allegedly not supposed to ship them casually like that. There have been many discussions on CPF about this. Those markers are supposed to be used only at fixed locations (light switch yes, bugout bag no) and the locations are supposed to be registered with the Nuclear Regulatory Commission.

What you want for a BOB or flashlight is called a glowring. That's just a little tritium tube in a plastic capsule about an inch long, with a small split ring attached, for use as a keychain marker. They are illegal in the US but you can buy them retail in the UK and various other countries--go figure. They are pretty easy to find on ebay and on the CPF buy/sell/trade section (a guy from Singapore sells them there). The larger markers also show up on ebay. What will we tell the children? :shrug: