toughest laser sights

I currently have a j-frame SW revolver that I keep in my car. I would like to purchase a laser sight for it, but I know that most laser sights do not work in extreme temperatures. I live in northern Alabama where summer temps reach up to 100 (about 130 in a car parked in the sun) and winter temps reach as low 15. Are there any laser sights out there that can handle these extreme temperatures?

The weakest part of almost all electronic devices is the battery/batteries. Crimson Trace claims that their lasers will perform properly in a temperature range of -10 degrees F to +120 degrees F before the batteries will fail. They also state that their laser grips have a melting point of +360 degrees F. This should be fairly close to or surpassing the extremes you experience and as long as your batteries remain fresh, it appears that one of the Crimson Trace laser grip products should work for you.