🖱️ BT21 BABY WIRELESS SILENT MOUSE : BT21 and Royche Collaboration Wireless Silent Mouse 🔋 BATTERY : Uses One AA battery 🔇SILENT CLICK : Noise is not occer even when used in a quiet place. 📡 LONG WIRELESS RANGE : 20m, 66ft 📏 SIZE : 113 x 64 x 31 mm, 4.4 x 2.5 x 1.2 inch