Review on SUNER POWER Battery Charger Maintainer by Rey High

I installed it in October so we are already getting less sunlight per day. I was hoping this would keep the battery fully charged, but it still drains to around 60-70% every few weeks, so I have to use a wall charger as well. Maybe it works better when there is more daylight. I aimed it directly at the southern sky using suction cups for maximum windshield effect.