Retaining Ring for Plastic Baffle in E-47/ 57 / 58H units. Mounts on Tank Stud. Sold in pairs. Might be Zinc Plated, or Phosphate (black). New LOWER price! (Was $5.50). Zinc plated resists rust better than Phosphate. When Phosphate inventory runs out we will begin shipping the Zinc plated. Click on Related Products tab for Bulk (50) Pack.