... compeitive price 3.high quality 4.matte surface industrial keyboard Membrane switch Multicolored printed ,embossedAppearance, long life, resistance ... for force15 ~ 750g forceconductive silver paste migrationin 55 ° C, a temperature of 90%, after 56 hours, the ... constantly.Environmental performance Operating Temperature-20 °C ~ +70 °Cstorage temperature-40 ° C to +85 ° C temperature 95% ± 5%large gas ...