My old reliable charger is a Schauer 10 a. 6 or 12 v. charger with automatic rate setting- starts at higher amps if battery is far down then tapers off. No timer needed and believe most current models are that way? metal case 30 yrs old made in cincinatti ohio. Yes it takes a day to fully charge a battery but will start a car after a night usually. But at $75 and one of the big name chargers I would go walmart. In fact I may update my old reliable!!!! Think U R paying some for the NAPA item. And Walmart has a good reputation for backing the items they sell. But with a Schumacher I would not worry, esp if they are still made in USofA. Lars |