The Biggest Problem With 日本人 インスタ フォロワー, And How You Can Fix It
http://juliusjmho637.tearosediner.net/5-killer-quora-answers-on-insuta-forowa-gou-ru-ri-ben-ren
Even cables with developed-in repeaters frequently enable for an external electric power source being connected. This is just a bit further safety for the sign and may be a good idea depending on the predicament