text: With the addition of retroreflective collars , traffic cones meet the requirements in the US Federal Highway Administration 's Manual on Uniform Traffic Control Devices ( MUTCD ) , which was amended in 1989 to mandate increased night-time visibility via the placement of additional reflective white bands on cones . Reflective collars , white strips made from white reflective plastic , slip over cones snugly , and tape or adhesive can be used to attach the collars to the cones permanently .
simplified: Many types of traffic cones have reflective strips or stripes of reflective paint , so that the cones are easier to see at night .