Seatbelts normally lock-fast when they recieve a certain amount of force. Occam's seatbelt will geometrically tighten upon impact so as to reduce the shock your body experiences normally(in a crash when the seatbelt locks).-- Trodden, Jul 17 2003 Dog Seat Belt http://www.pettails.com/petseatbelt.htmlFor [po]. Er, not *for* [po], but because [po] asked. [phoenix, Oct 04 2004, last modified Oct 21 2004] All other things being equal, the occupied seatbelt is the tightest.-- egbert, Jul 17 2003 Most seat-belts these days actually pull the seatbelt tighter in a crash. They work better this way.-- silverstormer, Jul 17 2003 yeah, it's baked, seat belts pre-tension nowadays. not sure if they do it geometerically though.-- neilp, Jul 17 2003 can you get a seatbelt for a dog?-- po, Jul 17 2003 Attach its lead to the grab handle. (Sorry Eric, don't mean it really).-- egbert, Jul 17 2003 Don't the belts stretch a bit anyway to reduce the shock? A bit like climbing ropes but less so.-- Gordon Comstock, Jul 17 2003 I was involved in a head on collision last year. My seatbelt saved my life. With the force of the impact the seatbelt melted to the top I was wearing at the time.-- silverstormer, Jul 17 2003 {{{shiver}}} poor old you.-- po, Jul 17 2003 [po] You don't know the half of it.-- silverstormer, Jul 17 2003 [po] Yes.-- phoenix, Jul 17 2003 random, halfbakery