Features: brand new and high quality Transmission rate: 3MBPS (MAX). Transmission frequency: 2.403~2.480GHZ. This product is suitable for windows7/8/8.1/10/Win11 system. Product Dimension: approx. 15x14cx5.5mm/0.59x0.55x0.22inches. Package Includes: neutral English, CD-ROM + manual + blister + cardboard packaging. Specifications: Product name: Bt USB Adapter Chip: RTL8761B Interface: USB2.0 Bt version: 5.1 Transmission frequency: 2.403~2.480GHZ Transmission rate: 3MBPS (MAX) Transmission distance: 10-20M unobstructed Support system: WIN7/8 / 8/ 8.1/10/Win11 Material: ABS Color: As the Picture Shows Product Dimension: approx. 15x14cx5.5mm/0.59x0.55x0.22inches Net Weight: 80g/0.18lbs Note: Please allow 1-2cm errors due to manual measurement. Due to the difference between different monitors, the picture may not reflect the actual color of the item. Package includes: 1x Wireless Audio Transmitter