Each option of ABC BirdTape provides a visual queue on the exterior of the glass that alerts birds to the presence of a solid barrier they cannot fly through. Birds perceive the tape as a solid object; if applied correctly, the spaces left between the designs are too small to fly through.The ¾” Tape x 50 feet covers approx. 13.5 square feet per package and is available in White or Light Blue.The 2” Squares x 50 feet covers approx. 27 square feet per package and is available in White or Light Blue.ABC BirdTape will last at least four years once installed.Installation instructions are available online.Manufactured and distributed by Feather Friendly.Sold on by conservation-photographers Kamala and Kyle Photography.