Abstract: The present invention relates to a rotational jack socket assembly which generally comprises a housing which has a jack socket rotationally mounted therein. The jack socket is provided will a receptacle for receiving and retaining a jack thereof The bottom of the housing is attached with a mounting bracket. The outer peripheral wall of the jack socket is alternatively enveloped with an annular terminal and an insulator. The housing is provided with a plurality of retaining holes which are corresponding to each of the annular terminals. Each of the retaining holes is further mounted with a resilient conducting loop which is provided with a plurality of projections which direct radially and inward. When each of the conducting loop is enveloped onto the outer peripheral of the housing, each of the projections can be suitably positioned within a corresponding retaining hole such that the projection is electrically contacted with the outer peripheral of the annular terminal.

Abstract: A quick stand adjusting device for adjusting the height of the stand of a ladder, a chair, an instrument or equipment, comprising a split retainer controlled by a control device, which is comprised of a crank, a transmission rod and a movable stop block, to move in and out of a recessed chamber in a lock socket at the bottom so as to engage or release a support which is extendibly inserted in the stand.