With that spot trace you have to use the batteries they suggest. If you use another battery you will only get about 3 months if your lucky the recommended batteries you will get 6 months plus. Was a good little unit when i used it. Only reason i got rid of it as i thought i was getting a insurance break for having a tracker installed in my machine and in the end their was no discount... If i was to hook it back up i would hard wire it just to eliminate the batteries since its so small you can hide it anyware and make it look like part of the unit... I hid mine in plane sight and even people that knew i had it never found it