Elmer's Washable School Glue Pens with Precision Tips #1 Teacher Brand (3-pens Per Pack) - 4 Packs #1 Teacher Brand Elmer's Washable School Glue Pens with Precision Tip. Dries clear, it is safe and non-toxic. Note: Not use with photos, bare metal, submerged or heater surfaces. Keep from freezing. Bonds most porous materials such as paper and cloth, and semi-porous meterials such as wood and pottery. To open, pull cap straight off. Push cap firmly in place until it clicks to close. Warning: choking hazard - small parts. Not for children under 3 years.