does anyone have an online source for replacement batteries?
Just last month I ordered 2 new batteries for $24.64 and a new sensor tip for $17.76. With shipping and handling everything was $51.12 at NTXTools.
Wow, I’ve had mine for 7 years and its still kicking with original factory parts.
Mine seems to never need charging.
Hmmm guess I better check,as I have not smelled gas lately.
Robert be aware that new sealant will set it off when inspecting and your nose is the first clue.
Does it still beep? 
Mine lasted over 5 years before needing new batteries. Some recommend replacing the sensing tip every 12-18 months depending upon usage.
i left it in my truck for about 3 weeks and the battery went completely dead, i think i fried it. I attempted to recharge and the battery light is weak and the ticking cant be turned all the way off.
That’s ok Mike.
I can be like that guy from Police Academy and just point as I go Beep-Beep-Beep.
Preceded by a radar sound of course.