Bostik Blu Tack Squares Blue 38g (Pack 12) Bostik Blu Tack is the original reusable adhesive. Bostik Blu Tack is clean, safe and easy to use and provides an ideal alternative to drawing pins or sticky tape. It has over a thousand uses around the home, office and school, which include holding up posters, card, paper, party decorations, etc., sticking down objects to desks and shelves, photos in albums, screws to screwdrivers, and much more. Bostik Blu Tack is CE approved. Recommended for use on non-porous surfaces.