AmazonBasics Ni-MH AA & AAA Battery Charger With USB Port 4-hour Ni-MH battery charger with USB charge port Recharges 2 or 4 AA / AAA Ni-MH batteries at a time Protects against wrong polarity charging and over charging Built-in switching power technology for worldwide use (100-240 V AC) Retractable AC plug; slim profile; ideal for travel