Thermo Sleeves

Construction Features

The Flexmaster U.S.A.® Thermo Sleeve contains the insulation and outer jacket only. It is made to easily slip over flexible air duct.

Vapor Barrier

Available in a black polyethylene or reinforced aluminum material. Both are fire retardant, have excellent strength at low temperatures, and will not age harden.
Type TSB
Fire-Retardant
Polyethylene Outer
Perm. rating = .10 grains
per square foot, per hour,
per inch of mercury		 Type TSM
Reinforced, Metalized
Outer Jacket
Perm. rating = .05 grains
per square foot, per hour,
per inch of mercury


Available in 25 ft Standard Lengths
Sizes to cover diameters from 4" thru 10", 12", 14", 15", 16", 18", 20", 24"

Insulation Options: R4.2 F R6.0 F R8.0