VERMEER SILVER SERIES DRILL RODS COMPOSED OF S135 COMMON GRADE STEEL
Vermeer’s Silver Series drill rod is composed of S135 common grade steel and is threaded in the same facility as the company’s Firestick drill rod with the same column wall thickness.
The Silver Series drill rod is available in four sizes: 1.66-inch, 1.9-inch, 2.06-inch, and 2.375-inch, for use on the D7x11 through the D24x40 S3 Navigator HDD models, including all current and legacy models in between.
fuente: https://www.constructionequipment.com/vermeer-silver-series-drill-rods-composed-s135-common-grade-steel