Combination Dual Port Fast Charger, Port No. 1 Charges All Dewalt12V-20V Max Li-Ion Batteries, Port No. 2 Charges All Dewalt 7.2V-18V NiCd/NiMH/Li-Ion Batteries, Except Univolt Batteries, Charges The Batteries In 1 Hour Or Less Thus Minimizing Downtime, Diagnostics With LED Indicator Communicates Battery Charge Status: Charged, Charging, Power Line Problem, Battery Too Hot Or Too Cold & Problem Pack Or Charger.