The 3690-500 from Holland Shielding Systems is a Microwave Absorber with Absorption 20 to 50 dB, Frequency 80 MHz to 100 GHz, Power 4 kW, Thickness 27.16 Inch/690 mm, Thickness 27.16 Inch. Tags: Pyramid, Power Absorber. More details for 3690-500 can be seen below.