The Hilti 18-36-Volt Lithium-Ion 4/36-90 Compact Fast Charger is the essential charger to keep your line of 18-Volt Lithium-Ion Hilti tools operating. Not only does it charge your Hilti lithium ion batteries, but it also tells you when they are ready. Constant LED lights indicate it is ready for use, blinking LED lights indicates the battery is too cold or too hot and is not charged, and no LED lights indicate the charger is not connected or not functioning. Get this Compact Fast Charger today to keep your 18-Volt Lithium-Ion Hilti tools charged and ready to use.