Mine roof warning indicator
FIG. 1 is a prospective view of the mine roof warning indicator showing our new design. 
     FIG. 2 is a perspective view with the indicator means in the danger warning position of the mine roof warning indicator showing our new design. 
     FIG. 3 is a top view of the mine roof warning indicator showing our new design. 
     FIG. 4 is a bottom view of a mine roof warning indicator showing our new design.