A single-acting O-Ring energized rod seal for dynamic applications installed in closed grooves, including grooves to ISO 7425. Stepseal® 2K offers high sealing efficiency, low friction with no stick-slip, minimal breakout force and high wear resistance. Optimum sealing characteristics are achieved by installing in a tandem Stepseal® or Rimseal arrangement together with a double-acting scraper. Available in Turcon® or Zurcon® materials.