Nitecore NL166 650mAh Rechargeable Li-ion RCR123A 16340 Battery, Yellow, 6952506490318. These batteries by Nitecore are made of lithium ion and useful for powering up your various Nitecore gear. Specifications for Nitecore NL166 650mAh Rechargeable Li-ion RCR123A 16340 Battery: Manufacturer: Nitecor