Use these film wipes to remove impurities from your Kelway HB-2 Soil Acidity and Moisture Tester. Each package contains 24 wipes. Cleanliness is vital to maintaining your meter's accuracy in the field. To use, wipe off your meter with a clean cloth, then place the conditioning film between the meters 2 metal plates. Be sure to place one film on each side of the lower part of the housing. Then squeeze the film lightly and rotate a few times. Take care to avoid touching the metal plates with your fingers.