We've used these ourselves for several years, and they've proven to be strong, light, and reliable. Drops over 5.5 lbs. off the 390 Duke or RC. 275 CCA. 3 year warranty. $159
www.mnnthbx.com
www.mnnthbx.com
We stock 4 cells as well (Grom page), but I'm not recommending them for the 390. The 4 cell may indeed start it, but it's not up to spec for the job, so I can't support it as such...I'm actually using a 4 cell and it works just fine.
I'm actually using a 4 cell and it works just fine.
I'm actually using a 4 cell and it works just fine.
We stock 4 cells as well (Grom page), but I'm not recommending them for the 390. The 4 cell may indeed start it, but it's not up to spec for the job, so I can't support it as such...
My ballastic 4 cell went for a toss rather quickly. But that might be because I let it sit for too long without charging.