To improve the grasp on the tongue of a seat belt, a handle extends from the seat belt tongue in the forward direction of the seat belt and is attached in a rotating manner to the central or rear portion of the tongue to perform rotation of the tongue in relation to the handle when the handle is grasped and pulled forward to fasten the seat belt. The synchronization can be accomplished without any external components. The wheels of the engine generator are disposed farther outward than the outer shell of the soundproof type engine generator. A method and devices are disclosed wherein stress is induced and managed in a thin film of titania in order to shift and lower the bandgap energy into the longer wavelengths that are more abundant in sunlight.