Great product.

Rechargeable AAAA Batteries The AAAA Ni-MH batteries cell 1.2V400mAh, 35-45min fast charging and up to 1200 cycles, no need to buy batteries frequently. We suggest every 3 months to charge the battery to protect the battery with more long life.. Energy Saving ECO Friendly Cadmium and Lead are not used in these batteries ANVOW AAAA batteries can be recharged 1000 times, saving thousands of alkaline batteries and reducing a significant about of landfill waste.. AAAA Batteries for Surface Pen ANVOW Rechargeable AAAA Batteries are compatible with Surface Pen and most Active Stylus. Note There are a small number of stylus pens that require 1.5V battery. At this time, the battery need to be fully charged before using it.. Package Included 2 x Rechargeable AAAA batteries, 1 x User manual and lifetime technical support providrd by ANVOW..