CellWrite Portable Bluetooth Folding Mouse Designed for Comfort, Folds for Portability, Folds to almost half of its fully expanded size, the mouse turns off automatically when it is folded. Pair with your Bluetooth Cell Phone or Tablet and use it On The Go (OTG) Part of the CellWrite OTG Package Kit (ASIN# B01GW6QKOK), We Are A Local Company with Domestic Delivery Options Up to 10 meters Wireless Operation Distance Optical technology, Uses 2 AAA Batteries (not included)