The 3640-1200 from Holland Shielding Systems is a Microwave Absorber with Absorption 5 to 50 dB, Frequency 30 MHz to 110 GHz, Power 1.5 kW, Thickness 47.24 Inch/1200 mm, Thickness 47.24 Inch. Tags: Ferrite, Pyramid, Foam Absorber. More details for 3640-1200 can be seen below.