In the development of thin and medium-power steeply dipping seams systems with long cleaning faces on the dip the most labor-intensive and heavy is the fastening of bottom-hole space, which takes up to 55-60% of working time.

To reduce coal losses at hydraulic development of powerful steeply falling seams by the system of sub-stage hydraulic stripping flexible metal overlaps are used, separating coal from the collapsed rock and, along with the completeness of extraction, allowing to carry out coal excavation in the absence of fasteners in the clearing space.