Carrying around a bunch of unnecessary weight is hard on parts.. I recently switched out my red tops.. to a pair of Antigravity 720's we took the car out for a weekend of racing.. and ended up running just a single battery. That only weighed 3 lb.. these batteries are amazing.. today I picked up a 780 to do some more testing. It weighs approximately 4 lb.. they get a little nervous because I don't have an alternator.. but so far so good