ERAYAK Smart Battery Charger 12Volt 1A Automatic Battery Maintainer Fast Charging Portable Trickle Charger with Detection & Repair Function for Car Boat Lawn Mower Marine 12V battery charger and maintainer from 2-40Ah, maintenance charge to 100Ah; No sparks, short-circuit proof and reverse polarity protected makes it safe for all the vehicles electronics and easy to use Fully automatic charging and maintenance in 6 steps maximizes battery life and performance; unique maintenance charging, a mode for optimized charging during cold winter days and the charging of demanding AGM batteries (i.e. Optima) Unique LED display allows the user to follow the entire charging process and provide visual state-of-charge feedback and diagnostic information Portable and lightweight, this smart battery charger can be stored anywhere; Water and dust resistant(IP65) means it is safe to use in all climate situations Numerous accessories simplifies using the same charger for multiple battery applications. One year limited warranty and 100% service, hassle-free return or refund for any product quality issue.