A C-29? Never heard of that. Thanks, I'll look for that one. Say they have 'em at WalMart? I've got an old battery charger at the marina I usually plug in the night before I go fishing & let it slow charge all night & I check the battery water pretty often. I think I've heard of the onboard charger from our marina guy. Is that the one that pigtails off your main boat battery and recharges as your running the motor? I've thought about that but was afraid it might run the main battery down. Wouldn't want to be out on the river & my main battery go down. Where can you get one? I might check into one.