... ,acid and alkaline-proof ,high dustproof USB flexible keyboard: anti-pollution, watertightness, acid adn alkaline-proof, ... the button bears to rype 2 million times.the keyboard is applicable to office ,hospital classroom, workshop, ... room, notebook PC, army etc. specification:Compatinility:IBM Windows98/2000/Me/XP Commvnication:USB,PS2,USB+PS ... data:+5V DC±%@250mA otal travel:2mm±4 Wight(kg):0.18