Amazon.com: YongerTool 5.0Ah BL1850B Battery Replacement for Makita 18V Battery,5000mAh High Capacity Compatible with Makita LXT Lithium Ion Battery BL1815B BL1840B BL1830B BL1820B,2 Pack with Mount Holder : Tools & Home Improvement
Amazon.com: Amityke Battery Adapter,Power Wheels Adapter for Makita 18V/14.4V Battery BL1820, BL1830, BL1840, BL1850 with 14 awg Wires Power Convertor for DIY Ride On Truck, Robotics, RC Toys and Work Lights :
2 Packs Replace for Makita 18V Battery 6.0Ah, Replacement Makita 18 Volt BL1860B Batteries BL1820B 1830B 1840B 1850B, Compatible with Makita 18v Tools, Fit with Original Makita 18v Battery Charger