The video-detection robot has both front and behind color cameras with 410 TV lines. There are also lights at the front and behind. The LED light makes the camera take more clear and presice pictures. The pitch angle of front camera is 100°,which expand the visible area. The body is made of aluminum alloy and has been treated with special technology, so it is very durable and corrosion-proof. It is small and easy to operate. Powerfull walking motor make it have strong crossing obstruction ability.The duct can be viewed and examined directly by it.