Porelon replacement pad only This pocket-sized replacement pad is the accepted STANDARD by law enforcement world wide Each pad may be used to record thousands of fingerprints A two-year supply of ink is impregnated in each pad (based on 75°F with lid closed after use), and is excellent for use in the field or officeThe thermal-impregnated fingerprint ink is non-fading and dries on-contact in seconds Ink rises to the surface as required through capillary action of the micro reticulated thermoplastic resin