DuFLine® expansion bellows comes with PTFE lining material (ASTM D4895), with lining and testing conforming to ASTM F1545-15a. Each unit undergoes rigorous hydrostatic testing at 1.5 times its pressure rating and flex-life performance testing to validate durability under allowable compression and extension cycles.

The product is coated with heat-resistant black paint, and options are available for stainless steel flange materials.