Spiral Pile for Ground Solar Mounting Bracket

The grounding screw are suitable for most following land: 
1) Topsoil: Sand, gravel, silt.   
2) Flowing sand: Liquid and muddy ground water.   
3) Friable soil: Loose sand, Gravel or mixed.   
4) Middle heavy friable soil: Sand, gravel, silt and clay.   
5) Difficult soils: More than 30% are stone which diameter bigger than 63mm.   
6) Moveable chisley soil: With rock, fay, crispness, slate, rotten soil.   
7) Moveable stereoplasm rock: Little rock with high structural strength jointed and weather-defined    8) picture