This 18-Key Numeric Keypad only weighs a quarter of a pound and is less than three-and-a-half inches wide which makes it extremely portable and space-saving. The keyboard's spill-resistant design helps to prevent fluids from staying inside, which would otherwise cause damage to the keyboard. Membrane key switches provide a quieter typing experience with lifecycle lasting up to five million keystrokes. This Numeric Keypad does not require a driver, simply connect the USB connector into your computer and it is plug-and-play.