Contoured, wave-shaped keyboard supports the varied length of your fingers for superior comfort and control. Three adjustable heights allow for a more comfortable wrist and hand placement while typing. Tiny LogitechÂ® Unifying receiver. receiver stays plugged into your laptop's USB port and lets you connect up to six compatible devices. 2.4 GHz wireless technology provides reliability and freedom without delays or dropouts. Extended battery life means longer use for up to three years without battery replacement.