A safety mat securement assembly for providing an open and a closed position for a climbing wall assembly using a safety mat. More specifically, a light shielding layer and an interlayer insulating layer are sequentially formed on a substrate, and then sourcedrain electrodes are formed on the interlayer insulating layer. A groove is circumferentially located about the cylindrical housing. The apparatus facilitates a rotating spindle grasping and rotating a work piece to be brought into contact with a processing tool held stationary on a work table. The storage device may have a capacitor, a rechargeable battery, a non-chargeable battery, a solar cell, fuel cell, line power, andor the like. Each shading sample location is associated with one or more of the depth sample locations.