On various calls I have been forced to break either car or building windows. I have used either a Monadnock PR-24 or a Monadnock AutoLock, the former was past issue and the latter is current issue. Neither was designed for this task. I have a scar to prove it.
Bust a Cap, Inc. is a company that manufactures a device that serves as an end-cap to several standard issue flashlights and batons. The cap replaces the threaded end. It is made of special steel that is made specifically for breaking glass.
Bust a Caps, which are made in the USA, are available for Streamlight and Maglite flashlights. They are also made for ASP batons. Because my Autolock has a release button on the tail, it is not compatible with the Bust a Cap.