A rollsign, roll sign, bus blind, destination blind or destination film's a mechanical display used to indicate the destination. They're commonly seen in older city buses, trams and subway cars. As a part of the contract, they're standard on London bus routes. Modern equipment substitutes a digital display in place of a rollsign, but the long life of these vehicles ensures that many systems continue to use these devices. Operation Names of the route or destination are printed on a long sheet… (More on Rollsign)