Product review (5 stars): Geat product -
Worked very well.  The rods are flexable, but rigid enough to push or pull the cloggs out of the dryer pipe.  If you are not able to push with the brush on the front, reverse the procedure and push the rod out to the outside and pull the brush through.  If the pipe is clogged, repeat the process multiple times.  After breaking up the clog, I used an electric leaf blower and blew the clog out of the pipe.  I also made sure the space was sealed between the leaf blower pipe and the dryer pipe.  Make sure you blow out to the yard and not the house.  It's a big mess.