I think Buffalo means 12 volt 1.5 amp charger/maintainer.....Schumacher also make good chargers. I have a Schumacher XM1 1.5 volt charger that I bought at WalMart for about $20 that I use on my bike batteries.
The battery tender junior comes with a fused pigtail connector that can be permanently attached to your battery. My tender is always keeping the battery at full charge both in the warmer and colder months of the year. And believe me, this winter it has been cold and the tender has done its job.What are good slow battery chargers for a new battery that has not been charged yet.