According to the invention, the pipe (3) with a lower diameter is placed in the pipe with a larger diameter in order to form a double pipe spay system.

The double pipe (92) includes an inner pipe (94b) as a passage of water and an outer pipe (94a) as a passage of a raw fuel.

An outer pipe (3) is provided at the junction between the steel pipe (2) and the stave body (1) to provide a double-pipe structure.

A balloon catheter can be easily produced by using this double tube.

A double pipe heat exchanger according to the present invention is provided with outer and inner pipes.

A double-pipe damping anti-bouncing upper wheel device comprises a double-pipe damping anti-bouncing upper wheel component (10) and a shifting piece (20).

The case (2) is a double pipe (24) upstream and downstream of the heating element (4).

The double-pipe damping anti-bouncing upper wheel device is convenient to mount and use.

Striking M Performance look for the rear of the car (twin tailpipe).

Heinke build also a very popular twin hose regulator, the Merlin.

The method involves connecting and disconnecting inner shafts and outer shafts of the dual pipe drill string.