Mice & Trackballs Features:Mini receiverSlip battery coverWide wheelMove freely in 10 meter's areaErgonomic battery cover design, easy to operate.Powered by 2 x AAA batteries (Battery NOT included)With LED indicator. When it is folded,it sleepsto stop working. When unfolded, it continues to work. Battery status indicator:If battery is in low power, the indicator will bered. Computer Connection:Wirele Wirele transmiion frequency: 2.4GHzType:Optical MouseOptical Resolution:1200 (dpi)Key number:3 (key)SupportsOS:Windows 2000/ Vista / Win7 / Win8 Applicable models:desktop, laptop 1,We are pure-heart seller and our goal is 5 STARS.We hope to provide you with the best products and best service,And strive for 100% customer satisfaction!2,When you receive the product, if you are satisfied with this product,Please kindly leave us positive feedback, we will try our best to do better.3,If you have any problem with the item,Please do contact us in advance before leaving any negative/neutral feedback.we can always try our best to Provide a good solution.so that we can satisfactorily addre your concerns.4,Good communcation is important for us. We are for sure can make it a succeful transaction for you. It is impoible to addre iues if we do not know about them!