... domes 2.Storage temperature: -40oC - +85oC 3.With transparent windows Membrane keboard advantages: 1.Beautiful appearance, rich and bright in color ... , acid and alkali proof, quakeproof. 5. Low cost, high lifespan, membrane switchs design and manufacture are using the keyboard as a ... costs are lowest,the life expectancy of different types of membrane switch is more than 100 million times. 6. Easy to ...