- Class 10 clean tunnel for cleaning, assembly, test and packaging operations. - Electropolished internal finishes as low as 7 Ra microinch or less. - Standard free poppeet design. Optional Tied Diaphragm design for positive shutoff also available. - 316L stainless steel coustruction or Hastelloyⓡ C-22 available. - Leakage 1 x 10-10 atm x cc / sec. He