Abstract: A fastener device includes two fastening elements, one or more slider members slidably engaged onto the fastening elements for securing the fastening elements together, and a warning device having a detecting device which may include two detecting members attached to either of the slider members or a support member and selectively engageable with other, and a signal generating device coupled to the detecting device for generating a warning signal when the detecting members have not been contacted with each other and for preventing the fastener device from being opened by unauthorized persons.

Abstract: This invention relates to a detachable mobile sound source structure, which is able to be formed as either a U-shape ribbon or two sound units, comprising two loudspeakers and a pocket that is used for containing playback equipment, e.g., MP3, etc. By means of the connection of a signal output line and said loudspeakers, the detachable mobile sound source device has a coupling component disposed thereon to be attached to a backpack or shoulder straps; Accordingly, the invention provides a detachable mobile sound source device enabling a user to listen to music or broadcast from playback equipment while on the move.

Abstract: This invention relates to a backpack light-emitting device, comprising a lighting panel having a LED in three primary colors and a control circuit fixed on one lateral side thereof. The lighting panel has a sheer logo pasted on the rear side thereof; the sheer logo is able to be fixed on the exterior of the backpack with a hollow portion disposed corresponding to the position of the sheer logo on the backpack, of which on the interior has a bag disposed corresponding to the hollow portion, thereby enabling the hollow portion and the lighting panel to be pasted on the rear side of the sheer logo. With the light-emitting of the LED in three primary colors and under the control of the control circuit, the invention enables the lighting panel to luminesce different colors in circules, in addition, emits light outwards via the sheer logo.