Supply of Plastic cover 4 Aspect Signal unit cover operated from front side & bottom side made of black polythene sheet of 100 micron thickness size of 1700mm x 460mm x 205mm and back side 75mm wide corner to corner diagonal cross mark of silver of 100 micron thickness to be provided to the UP cover with signal unit suitable to nylon rope of 5 mm dia and 4 mtr length of 1. 5 mtr length at the center.