Item # Description Case Pack
  5150BM00-20R 20mm Red BiMetal Seal, 0.100″ PTFE/Silicone  100 View Product
  5150BM00-20B 20mm Blue BiMetal Seal, 0.100″ PTFE/Silicone  100 View Product
  5150BM18-20R 20mm Red BiMetal Seal, 0.118″ PTFE/Silicone  100 View Product
  5150BM18-20B 20mm Blue BiMetal Seal, 0.118″ PTFE/Silicone  100 View Product
  5150BMUL-20B 20mm Blue BiMetal Seal, 3mm Thick Clear PTFE/Blue Silicone, Ultra Low Bleed 1000 pieces View Product

The BiMetal Seal is comprised of tin and aluminum materials. The outer surface (red or blue) is aluminum and the inner diameter is a silver tin.