What is a Flip-Stik flap?
Flip-Stik flaps have adhesive applied on two flaps and the flaps are separated until sealing.
Simple Seal envelopes are an example of an envelope with a flip-stik flap.

Flip-Stik flaps have adhesive applied on two flaps and the flaps are separated until sealing.
Simple Seal envelopes are an example of an envelope with a flip-stik flap.