The milwaukee m12 nrg 201 energy kit contains the following 1 x 12 volt m12 c12c li ion charger with a compact and lightweight design that gives you more runtime and power enabling you to work longer after charging cutting edge electronics eliminate memory effect the battery can be charged at any time without reducing the charging capacity constant fade free power throughout the discharge cycle redlithium ion 20ah battery packs recharge in 40 minutes or less 1 x 12 volt m12 b2 redlithium ion b