How much does this cost to the nearest dollar?

New F999B Super Sensitive Listen Thru-wall Contact/probe Microphone Amplifier System (Warranty period of five years)
The ultimate professional listen through wall system that can hear sound through concrete, metal, wood, brick in fact any solid surface. This serious piece of kit is not for the faint hearted, be warned you can hear through indoor and outdoor walls. Some surfaces work better than others and density / thickness can also restrict its performance. We have received varied results as it depends entirely on the surface you use and many other factors such as distance and volume. Place the Sonde contact microphone to the surface of interest and listen it has variable gain and volume settings. You may need to experiment further with the position for better results and we can not guarantee results first time every time.

Price is $136.00

Price: $135.99