"This Water Source Stainless Steel Well Point penetrates all types of soil, delivering a combination of easy driving, effective sand control, corrosion resistance and strength. Three-step bonding method prevents screen from pulling back. Pipe Diameter in. 1 1/4, Length in. 38, Material Stainless steel. Threaded octagon shoulder prevents turning while driving forms a hole large enough to allow clearance for pipe couplings 1 1/4in. inner diameter"