Tripp Lite KP3040 Notebook/Laptop Keypad with 2 USB & 2 Microsoft Hot Keys Device Type - Keypad SYSTEM REQUIREMENTS - Windows 95/98/ME/2000/XP , USB port Product Type - Notebook Keypad Programmable Buttons / Hot Keys - 2 Microsoft Office hot keys - Word and Excel Unit Dimensions (in) - 4.9 x 3.1 x 0.8 (L x W x H)