2Pack BL1840B 4.0Ah 18V Replacement Battery for Makita 18v Battery Lithium Compatible with Makita 18 Volt Battery BL1815 BL1820 BL1830 BL1840 BL1850 - - Amazon.com
Amazon.com: MAKITA 18V LXT Litio-ION 4.0AH (BL1840B) : Herramientas y Mejoras del Hogar
Amazon.com: MechanicAnts MA21007 Lithium-Ion 20V MAX 4.0Ah Battery for All MechanicAnts Power Tools, Compatible with Makita BL1840 : Tools & Home Improvement