The MR11-0003-20 from MAST Technologies is a Microwave Absorber with Frequency 3.0 GHz, Thickness 0.098 Inch/2.5 mm, Thickness 0.098 Inch, Thickness (mm) 2.5 mm, Operating Temperature -60 Degrees F to 375 Degrees F. Tags: Tuned Frequency Absorber. More details for MR11-0003-20 can be seen below.