looking a tracvk for 690a thanks
Good Gawd..... Even when I was turning wrenches back in the 80's those were dinosaurs.... we had a pair of 690B's which were obsolete when they were built, but still they were a much more modern track chain than the "A"s had. Try this: http://www.machinerytrader.com/list/dismantledsearch.aspx?ETID=3&Manu=DEERE&Mdltxt=690A&mdlx=exact