Jock, 6.4mm is 1/4", 5mm is .2" Not metric talk, just NASA talk....wait, they (messed) up the mars rover didnt they?
Either way, windshields are laminated to keep the rocks from hitting you in the head, the rest is tempered like Jock stated to pull ones back side from a wreck.
Last edited by cletis; 05/16/2009 3:40 AM. Reason: language