Detailed Product Description General Description:This is a Two -in - one device,It compatible PC Keypad and 12bit Commercial Calculator with TaxCalculation.1, The ... , Press ''MODE'' to choose the mode for operation . a.Connecting this device by USB cable to PC, it would show ''PC ... direction key.8,Size: 16*9.5*3.0cmcalculator Compatibility This device compatible WINDOWS ME,2000,XP,VISTA and MAC OS