1, according to the different standards of the quality, it can be divided into four types: g, g1, g11, g111. 2, different lengt drill rod features:1, high quality2, different lengths to meet your requirements3, the stainless steel materialdrill rod specification:1,Length: 1m,2m,3m etc.2, material: stainless steel3, processing type: castingdrill rod picture: Rock Drill Steel Rod