Milwaukee M12 and M18 12-Volt/18-Volt Lithium-Ion Multi-Voltage 6-Port Sequential Rapid Battery Charger (3 M12 and 3 M18 Ports) - Amazon.com
Amazon.com: 【Charge Choose Button & Wall Hole】 Replacement 6 Port Charger for Milwaukee 48-59-1806 18V M18 Six Port Lithium-Ion Charger Fast Charge with Power Button,6 LED Indicators : Tools & Home Improvement
18-volt six pack sequential charger
Milwaukee M18 18V Lithium-Ion 6-Port Sequential Battery Charger w/(2) M18 5.0Ah Batteries 48-59-1806-48-11-1850-48-11-1850 - The Home Depot