The MR31-0005-20 from MAST Technologies is a Microwave Absorber with Frequency 4 to 7 GHz, Thickness 0.060 Inch/1.5 mm, Thickness 0.060 Inch, Thickness (mm) 1.5 mm, Operating Temperature -60 Degrees F to 375 Degrees F. Tags: Surface Wave Absorber. More details for MR31-0005-20 can be seen below.