Abstract: A fastening and locking device structure, particularly for ski boots, comprises a hollow frusto-conical element enclosing the ski boot shell at a middle region thereof. The frusto-conical element extends at a top region into a tongue and laterally to the ski boot into two wings encircling the ski boot middle region and joining together in a groove provided between the sole and the heel region of the ski boot. The frusto-conical element is further fixedly connected with two lugs extending towards the boot heel, whereat they present a tension lever device for fastening them together and tightening the boot flaps.