Thermaflex M-KE Acoustical Flexible Air Duct- offers exceptional sound control.  Its acoustically rated chlorinated polyethylene (CPE) core allows sound energy transmission through the core and insulation, and into the plenum space.  A highly efficient, self-extinguishing duct, the M-KE is suitable for use in all pressure heating and cooling systems. 

• Size:  14" inside dia. x 25 feet per length
• Max. Positive Pressure:  10" water column (4" - 12" ID);  6" (14" - 16" ID); 4" water column (18"-20"ID) 
• Max. Negative Pressure: 1" water column (4"-12" ID); 1/2" water column (14-20"ID) 
• Velocity (feet per minute):  5,000 FPM 
• Temperature Range:  -20ºF  - 200º F cont.; -20ºF  - 250º F intermittent
• R-Value:  R-4.2, R-6.0, R-8.0