The invention discloses a bypass device which comprises a box body, a
front cover and a
handle. A lower-portion printing plate at the bottom of the box body comprises at least one lower-portion plug part, the
front cover is buckled and fixed to the box body, the
front cover is provided with an installing hole, and the top surface of the front cover is provided with position signs. The
handle is similar to the installing hole in
peripheral shape. At least one upper-portion plug part is fixed to the bottom surface of the
handle, and a bypass sign is arranged on the top surface. When the handle is embedded into the installing hole and the bypass sign corresponds to the different position signs, the upper-portion plug parts on the bottom surface of the handle are oppositely plugged with the lower-portion plug parts of the lower-portion printing plate, and different
external route communicating states are formed through different opposite-plugging combinations of the upper-portion plug parts and the lower-portion plug parts. The bypass device is convenient to use, and the plug parts are accurate in opposite plugging and positioning.