... and liquid-proof, meet IP65 requirement 6) PS/2 or USB interface, easy to plug into computers directly 7) Customizable Specifications:Material ... voltage: DC 5 V ± 5% - Current rating: 20 mA - Interface: USB or PS2 - EMC compliant. Emission: EN 50081-1 Immunity: EN ... Operation system - PS2: Win NT4, 98SE, 98ME, 2000, XP - USB: Win 98SE, 98ME, 2000, XP, Mac OS9 / OSX, Win7,Linux Reliability - MTBF > ...