Powerful radar shielding panels that are made from granite and lead, connected to a metal faraday cage through aluminum tape.
See the RADAR MICROWAVE TECHNOLOGY RESEARCH page for more on powerful radar assault shielding and attenuation.
Powerful radar attenuation consists of using dense materials, lead is used by the industry but toxic, a neuro-toxin, it gets into the brain and bones, adding barium to cement, cement density and metal content.
The cheapest powerful radar attenuation method is probably to buy several bags of granite or crushed stone. These can also be placed in free plastic containers and filled with water. The crushed stone and water help to shield from powerful radar through density and thickness but the water also helps to attenuate or shield from sound technology, the 2005 award winning HSS Hypersonic Sound technology, or Focused Ultra Sound used to "hit the heart or brain".