may be provided in the middle of the cords 61 of the connector a separate connector now shown which provides for an electrical connection and disconnection in figures the reference numeral 5 denotes a sealing member made of an elastic material such as epdm of a closed cell structure etc the sealing member 5 is shaped to have the form of a hollow cylinder of which the axial length is smaller than the radial dimension the sealing member 5 has formed in the center thereof an opening 50 in which the base 41 of the lamp bulb assembly 4 is water tightly fitted and through which the terminals 43 are passed the sealing member 5 is formed separately from the connector 7 and waterproof cover 7 before the terminals 43 of the lamp bulb assembly 4 are fitted into the connector 6 they are inserted into the opening 50 in the sealing member 5 the sealing member 5 is fitted on the outer circumference of the base 41 of the lamp bulb assembly 4 in a watertight manner and the front end of the sealing member 5 is pressed to the rear end of the boss 70 of the waterproof cover 7 in a watertight manner in this condition the rear end of the sealing member 5 extends somehow from the rear end of.