Features:OOTDTY   The latest Bluetooth-compatible 5.3 technology has made major breakthrough; optimizing the transmissiondelay and connection defects of the old version of Bluetooth-compatible5.0 USB Bluetooth-compatible 5.3 Adapter support downward compatible-bluetooth 2.0/3.0/4.0/5.0-/5.1 devices.Diver-free for Win8.1 and Later ;Only use on Windows- computer Bluetooth-compatible 5.3 high performance and stable transmission; durable. Plug play- it can connect 5 devices at the same time-.Specifications: Item: Usb Bluetooth-compatible 5.3 Receiverfor: computer laptop wireless keyboard mouse and moreColor: Black/White Material: Plastic+MetalSize: approx 31x15x11mm/1.22x0.59x0.43inQuantity: 1PCPackage Includes: 1 Piece Usb ReceiverNote: Due to the problems of lighting effects and shooting angles; there will be certain tolerances in the product; please understand.Please allow 0-1cm error due to the manual measurment.