Abstract: The present invention discloses a splicing type electret loudspeaker. The splicing type electret loudspeaker may comprise a plurality of electret loudspeaker units. Each electret loudspeaker unit may comprise a plurality of connection ports, and these connection ports may be disposed around the edge of each electret loudspeaker unit. In particular, the connection ports of each electret loudspeaker unit can respectively connect to one of the connection ports of another electret loudspeaker unit; in this way, these electret loudspeaker units can connect to each other in parallel, such that the power input signal and the audio input signal can be transmitted to all electret loudspeaker units to drive them.

Abstract: The present invention discloses a splicing type electret loudspeaker. The splicing type electret loudspeaker may comprise a plurality of electret loudspeaker units. Each electret loudspeaker unit may comprise a plurality of connection ports, and these connection ports may be disposed around the edge of each electret loudspeaker unit. In particular, the connection ports of each electret loudspeaker unit can respectively connect to one of the connection ports of another electret loudspeaker unit; in this way, these electret loudspeaker units can connect to each other in parallel, such that the power input signal and the audio input signal can be transmitted to all electret loudspeaker units to drive them.

Abstract: Provided is a luggage wheel system mounted at either rear corner of a luggage case, comprising a bracket fixedly secured to the luggage case, a spring-loaded wheel assembly rotatably disposed in the bracket, and a fender slidably disposed in a front portion of the bracket and above the wheel assembly in a nonoperating position. In a case of the wheel to be encountered an irregularity (e.g., crack, pebble) in the supporting surface a luggage user may lower the fender to disengage a top bent member of the fender with a latch in a wheel mount for covering a rear, upper half portion of the wheel. As an end, cuff of trousers worn by the luggage user is prevented from becoming dirty by contacting the wheel when lifting the luggage.