Brand: ELECOM Color: Black Connectivity Technology: USB, 2.4GHz Wireless Special Feature: Silent Buttons Movement Detection Technology: Optical Number of Buttons: 5 The "bitra" wireless mobile trackball, a thumb-operated type, achieves high operability despite its compact design, perfect for mobile use. [Connection Method] 2.4GHz Wireless (Receiver Included) [Number of Buttons] 5 buttons *Including wheel button Width: 73.7mm × Depth: 89.9mm × Height: 41.3mm [Power Supply] One AA alkaline battery, AA manganese battery, or AA nickel-metal hydride battery (Estimated battery life: approximately 110 days) 〇 The outer box was opened for the purpose of taking pictures of the contents, but the contents have not been taken out. 〇 Stored at home.