I have this older Black & Decker branded smart charger:
I bought it at Wally World many years ago, and I recall it being pretty cheap. However, it has been a great little charger. It will alert you if you connect the cables backwards, for example, and it will also only charge a battery to full. You can choose between three charge settings--10, 6, or 2 amps--and it will automatically step down as the battery nears full. Overall, I've really liked it for being such a cheap model. Having said that, I have finally decided that this model has two significant drawbacks:
#1: it cannot charge AGM batteries (I have one in the Jeep).
#2: it cannot charge a completely dead battery. There needs to be a minimum voltage amount for this charger to see, and if I'm below that threshold then this charger is completely worthless.
Based on those two drawbacks, if I were shopping for a charger today I would seriously consider the NOCO Genius10 that
@lhracing posted above.