I have one of these on my lightly driven 2000 Corvette and one on my boat. Son has one on Miata and friend has one, all work well.
MOTOPOWER MP00205C 12V 800mA Automatic Battery Charger, Battery Maintainer, Trickle Charger, and Battery Desulfator
https://www.amazon.com/gp/product/B07PG6RXLN/