The M18 REDLITHIUM XC5.0 10-Pack includes (10) M18 5.0Ah Battery Packs that deliver up to 2.5x more run-time than standard lithium. The packs deliver up to 20% more power than standard lithium which means faster application speed and increased application range for end users. With REDLITHIUM Protection the packs have industry leading protection against vibration/impact, water, and heat. M18 packs also have forward and backward compatibility with 125+ M18 tools.