Guys with more experience or more battery savvy than I possess may have already known this or it may come off as common sense, but I finally had to replace my Vex battery after 9 years of flawless performance. I shopped around for the best price. I run a vex FL-20 ultra pak. It has a 12v. 9 amp battery. The prices on line and at several sporting good stores ranged from 38.00-58.00. I was at the Wal mart and found they sell a game camera battery 12 v. but 7.5 amps. The price is 22.00. Same size as the Vex battery but considerably cheaper. I thought it may work, but wanted to be sure so I called the Vexilar 800 number and spoke to a technician and he stated that the only difference will be a sight decrease in run time on the 7.5 amp vs. the 9 amp. He thought maybe a day and a half of run time instead of the full 2 days. He claims that if you just recharged it every night (which I do anyway) there would be no performance issues. Again, this may make sense to most, but for those in my shoes this year, it may save some moolah!
