Even if the voltage on the bike side is stable, there is no problem in operation. Because it has a waterproof socket cover, there seems to be no problem if it is somewhat rainy. However, it is desirable to use it for vehicles with screens, since it is the origin of trouble that direct water is applied.
I bought it for attaching ETC to the bike. Because it is storage under the seat, waterproofness is not so much needed, but it is a problem that it does not matter if it is attached to the outside with a firm build. It was saved a bit more compactly, but since there are 2 branches, we can afford in the future and have peace of mind. Since taking out from the battery is a prerequisite, it may be easier to buy if there is a set display that makes it easy to purchase removal news etc.