Dab-and-Seal envelope moistener makes it easy to seal hundreds of envelopes quickly. Adhesive formula glues as it moistens to securely seal up to 1,500 envelopes per bottle. Patented spill-proof spring-valve applicator won't clog so envelope production keeps rolling along. Lab-tested formula: This non-toxic, non-flammable and water-soluble adhesive cleans up with a quick wipe and water. Ideal for office work including labels, stamps and mailers or for paper crafts and art projects. The only way to seal! Fast-drying nonflammable, non-toxic formula conforms to ASTM D-4236. Spring-valve applicator won't leak even when tipped over.