HM-101B Height Marker Door Strip (Set of 2) Black and White for Retail, Gas Stations, Convenience, Check Cashing, MORE! Mark your doors and vaults with these adhesive-backed strips to aid in determining intruder height identification. Height Markers can be placed in various locations including walls, doorways and vaults to aid employees, security personnel and police in the event of a robbery. Security height marker strips are commonly used in banks, credit unions, gas station, convenience stores and other retail locations. Even if a security camera is not openly visible near the door, height marker strips can help discourage a theft. Each set includes two easy-to-apply security height chart strips. Color: white with black height chart markers Markers range in height identification from 4.5′ to over 6.5′ Two adhesive-backed height markers per set 2 height markers per set