To simply cope with type change and to provide sure waterproof effect.

One rod-shaped member, for example a pad 5 of a fragment of a harness is bent in a U-shape, and its two ends are water-tightly, detachably inserted into two through holes 33 of a waterproof cap 3,300. When a type is changed, the pad 5 is drawn out of the through-holes 33, harnesses 44, 45 from a heater 252 are water-tightly inserted into the through-holes 33. Next, the harnesses 44, 45 from the heater 252 are drawn out of the through-holes 33 and the pad 5 is water-tightly, detachably inserted into the through-holes 33. Therefore, a device can simply cope with the type change. Since the pad 5 is surely inserted into the through-holes 33, the pad 5 and the waterproof cap 3,300 are surely, closely contacted, and sure waterproof effect can be obtained.