Hitech Smart Battery Charger/ Discharger: Capable of charging both NiMH and NiCd batteries, this charger is extremely versatile. Featuring two turn-dial options, a user is able to charge batteries as low as 2.4v and as high as 12 volts! Just turn the left dial to reflect how many cells your battery has and turn the right dial up to 600 mAh and your ready for some awesome charging action! This charger also features a discharge function that allows a user to charge a NiCd battery without worrying about switching devices or developing a memory. Simply plug the battery in and a red light will appear. Push and hold down the discharge button located in the bottom middle of the charger for about 2 to 3 second and lift. An orange/ yellow light will appear, indicating that your battery has begun the discharge cycle. When the red light reappears, your battery has finished discharging and is automatically on the charge cycle. When a green light appears the charger will automatically stop charging thus preventing any dangerous mishaps associated with overcharging/ overheating. To prevent any confusion, this charger is not capable of charging or discharging Li-po or Li-ion batteries. Risk or damage or fire is associated with this action.