Weighing only 2.14lb Bosch's CORE18V Lithium-Ion 8 Ah high power battery is an ideal balance of size, weight, power, and runtime.
CORE18V batteries are compatible with Bosch 18V Tools; optimized for Bosch PROFACTOR™ Tools for power comparable to the most demanding corded tools. Constructed using two layers of enhanced 21700 cells for greater battery efficiency. With its cutting-edge battery design – including copper end plates, power rails and a flexible circuit board – it offers reduced resistance and increased efficiency. Featuring exclusive CoolPack™ 2.0 technology, which cools the battery faster and helps provide longer lifetime. It includes a charge-status Indicator with high resolution for clear visibility. Connected-ready technology, and AMPShare System compatible. Bosch 18V 3 Year Battery Limited Warranty. Sold in a pack of 2 CORE18V® 8 Ah Batteries. Ship wt. 4.7b. 
WARNING: This product contains a chemical known to the State of California to cause cancer. For more information, please see www.P65Warnings.ca.gov