REUSABLE: Simply wipe it down with soap and water then store it in its case for future use. (Please notice keep away from sunlight and heat source). INSTANT READ: 35 Degree Celsius to 40 Degree Celsius;95 Degree Fahrnheit to 104 Fahrenheit,this temperature strips will show the current temp. INSTRUCTIONS FOR USE: STEP 1: Press firmly on the both sides of feverscan, to make sure it fully cover your forehead; STEP 2: The color sections would change in 10-15 seconds; STEP 3: The color change of highest temperature section is your current body temperature; Notice: The color changed section would be recovered in 2-5 seconds away from your body. EASY TO USE: Quickly Measure (about 15 Seconds). Some children or baby don't like to have probes in their mouths or other places. Just stick it on your baby's head(about 15 second) as an easy way to check on fevers. Note: Do not put it under the sunlight for long time. Do not use it within 30 minutes after meal, drinking and activity. 20PCS ESSENTIAL FOREHEAD THERMOMETER STRIP: Forehead temperature thermometer strip for use on children and the elderly, can be used with very little disturbance.