The Makita BL1850B is an 18V Lithium-Ion battery that is designed to be used with Makita's line of power tools. It is an updated version of the BL1850 battery and offers an increased runtime and lifespan.

The BL1850B battery has a 5.0Ah capacity, which means it can power your Makita tools for a longer period before requiring a recharge. Like the BL1860B, it also features an integrated L.E.D. battery charge level indicator that allows you to easily monitor the remaining battery life.

The BL1850B battery is built with Makita's Star Protection Computer Controls™, which are designed to protect the battery and tool from overloading, over-discharging, and overheating. This helps to extend the battery's lifespan and ensures that your Makita tools continue to perform optimally.

The Makita BL1850B battery is compatible with Makita's Rapid Optimum Charger (sold separately), which can charge the battery in as little as 45 minutes, depending on the charger model. It is also compatible with Makita's Dual-Port Rapid Charger, which can charge two batteries simultaneously.

Overall, the Makita BL1850B is a high-quality battery that provides longer runtime, greater durability, and advanced protection features, making it an excellent choice for powering your Makita tools. It is a popular choice among professionals and DIY enthusiasts alike.