Be careful with those. Plenty of cheap ones have metal hammers that will simply bounce off the window like the window was rubber (I assume the cause is wrong metal used, or point not sharp enough). And this is assuming tempered glass.
When AAA tested 3 different hammers, only 1 of the three successfully broke tempered glass. All three punch style tools broke the tempered glass.
But a lot of car windows now have laminated glass. While the tools may be able to shatter the glass for those, they still stay in one sheet, (just like shattered windshields in most car, since those are laminated glass too). And it is really hard to break through that shattered but still intact sheet, with neither style of escape tool really being much help.
When AAA tested 3 different hammers, only 1 of the three successfully broke tempered glass. All three punch style tools broke the tempered glass.
But a lot of car windows now have laminated glass. While the tools may be able to shatter the glass for those, they still stay in one sheet, (just like shattered windshields in most car, since those are laminated glass too). And it is really hard to break through that shattered but still intact sheet, with neither style of escape tool really being much help.