Quality Park Envelope Moistener makes for a useful addition to have in an office. It can be used to secure the inner flap of an envelope before mailing a letter. Use this moistener to eliminate the need for frequent licking. It features an adhesive that can be used to glue other paper products. This moistener is non-toxic and acid-free to ensure safe use. Thanks to a spring-valve applicator, it's easy to use and will not clog. This envelope moistener with adhesive comes in a 50mL bottle and can last long enough to moisten more than 1500 envelopes.