Do not use organic solvents or alcohol when cleaning the cover. Wipe off dirt with a solf, dry cloth.
When the surftest 211 and it accessories are not in use, they must be replaced in the case or similarly stored to avoid dust and humidity.
Store the instrument in a -10C to + 40C' temperature range to maintain battery performance. The surftest 211's self-contained batteries (sealed nickel cadmium type) are affected by ambient temperatures shortens battery life considerably.