This is a titanium rescue ring from TAD Gear, it has a removable spike that can be used to break glass windows in case of emergencies.The spike comes with an attachment base that has a hole for a splitring so you can put it in your keychain and use it only when needed, in case of need just unscrew the spike and screw it to the ring.
The Ring is made of titanium and the spike is stainless steel. Optionally you can screw an SS button compass instead of the spike and use the ring for navigation (compass not included).
As a piece of titanium jewelry the ring is really nice and confortable to use and compared to other Ti rings it is very affordable, offering the option of the spike as an emergency device in case of need. The threads to attach the spike to your keyring are not very long so with some time it will eventually get loose and you are in a big risk of losing the spike. Besides this problem it is not very clear how quickly you can get the spike ready in case of need if you are rescuing somebody it may help, if you are the one in need of a quick exit it is probably too slow and too small to be correctly operated during an emergency.
You can get it in sizes 5 to 13 from TAD Gear.