... Temperature-40°C~+85°CHumidity40°C,90%~95%,240hoursMembrane switch,membrane keypad,membrane keyboard Advantages:1. Beautiful appearance, rich and bright in ... harmful gases proof.5. Low cost, high lifespan, membrane switches design and manufacturer are using the keyboard as a whole way , ... costs are lowest ,the life expectancy of different types of membrane switch is more than 100 million times.6. East ...