The MR11-0004-20 from MAST Technologies is a Microwave Absorber with Frequency 4.0 GHz, Thickness 0.078 Inch/2.0 mm, Thickness 0.078 Inch, Thickness (mm) 2.0 mm, Operating Temperature -60 Degrees F to 375 Degrees F. Tags: Tuned Frequency Absorber. More details for MR11-0004-20 can be seen below.