· Compatible with Safe Home SH502 indoor fly trap and DynaTrap DOT bug light plug in.· Long-Lasting: It is possible to use the replacement sticky cards for up to 3 weeks. You will get 20 indoor fly trap refills.· Safety: The non-toxic and odorless glue is safe for everyone in the family. It will trap and securely hold insects.· Easy to Use: Peel off the plastic cover of glue boards before use. And then insert it into the trap.· NOTE: If you have any questions, please don't hesitate to contact us. We will be happy to provide a satisfactory solution.