R.D.S. String magnets are ran to ensure clean and obstruction free well bores.  The string magnet is a pump thru magnet that allows drilling fluids to circulate the well bore and catch debris.  Manufactured from 4140 HTSR steel tool joints, the stainless steel tubing section houses rare earth magnet inserts. This magnet has a very powerful draw that collects and retains metal contamination with out effecting fluid flow.