The HT220-50 from Withwave is a Microwave Absorber with Frequency DC to 36 GHz, Thickness 0.02 Inch/0.5 mm, Thickness 0.02 Inch, Thickness (mm) 0.5 mm, Resistance 1 x 10^6 Ohms. Tags: Cavity Resonance Absorber. More details for HT220-50 can be seen below.