Masscool NOTEPAD-WALK Aluminum Notebook Cooler Pad w/2 65mm Silent Fans & 2-Port USB 2.0 Hub (Charcoal Gray) Masscool NOTEPAD-WALK Aluminum Notebook Cooler Pad General Features: Charcoal gray color For notebook cooling Aluminum case Dual turbo fan design Two (2) USB 2.0/1.1 ports Extremely quiet On/Off power switch Portable design Lead-free Fan Specifications: Bearing: Hydro Bearing Rated speed: 2,000 10% RPM Rated voltage: 5VDC Starting voltage: 4VDC Operating voltage: 4.5 - 5VDC