This adapter can make lithium batteries compatible with Dewalt 20V Max tools and allow you to enjoy the benefits of extended run time of Li-lon batteries on your existing 18V tools. Features : 1. Allows the use of 18V lithium batteries and spare batteries in most Makita compatible batteries: BL1860B / BL1860 / BL1850B / BL1850 / BL1840 / BL1830B / BL1830 / BL1820 / BL1815 , etc. 2. The battery adapter can make lithium batteries compatible with Dewalt 20V Max tools that use a lithium battery. 3. The maximum initial battery voltage (measured with no load of working) is 20V, rated voltage is 18V. 4. Strong structure and ABS shell material design make it durable and easy to use. 5. Compact and portable, easy to install and disassemble, upgrade your old tools. Note: 1. Due to manual measurement, the size may be slightly different. Thanks for your understanding. 2. Due to different lighting conditions and different monitors, item color displayed in photos may be showing slightly different