The MR31-0006-20 from MAST Technologies is a Microwave Absorber with Frequency 3 to 6 GHz, Thickness 0.07 Inch/1.8 mm, Thickness 0.07 Inch, Thickness (mm) 1.8 mm, Operating Temperature -60 Degrees F to 375 Degrees F. Tags: Surface Wave Absorber. More details for MR31-0006-20 can be seen below.