Amazon.com: Enegitech 18V 4.0Ah Replacement Battery Lithium-ion 2 Pack BL1840B, Replace for BL1850B BL1860 BL1840 : Tools & Home Improvement
Amazon.com: Adapter Converter for Makita 18V BL1860 BL1850 BL1840 Li-ion Battery to Ridgid AEG 18V Hyper li-ion Power Tool Battery : Tools & Home Improvement