Product review (5 stars): An amazing vent-cleaning tool kit at a reasonable price!
I had not cleaned our dryer duct in 22 years!  I know, my bad.  It is 26' long (mostly horizontal), with 4) 90deg. bends (not including the 2 elbows in the vent pipe which connects the dryer to the wall), so it is far from the "ideal" vent system.

I had noticed that clothes were taking too long to dry in our Maytag gas dryer, so I did what has worked in the past - I replaced the coils on the gas valve, and even threw in a replacement operating (cycling) thermostat (which had never been replaced).  I did my normal cleaning of the internals of the dryer, including the filter housing; but still the dryer ran too long.

I looked into the outside dryer vent hood, and saw quite an accumulation of lint in the pipe, so I ordered this kit, plus the set of 4 extra rods, due to the length of the duct.  When the kit arrived, I began by attaching a shop vac to the inside end of the vent, and using the brush on a cordless drill from that end.  I used a dust collector drum between my shop vac and the vent, so that the shop vac would not get clogged up.  That worked great by the way!  Anyway, I was able to clean out the 1st 5' of the duct, including 2) 90deg. bends, but that's as far as I could get, the brush was up against an obstruction of some sort.

While the shop vac was running inside, I went outside and could not feel any suction at all at the vent hood, so I knew I had a major blockage.  I left the shop vac running inside, and started using the brush from the outside.  I encountered 2 more 90deg. bends just inside the house, then a long straight run.  I slowly added rods until I had 7 rods in the duct, where I hit the blockage I had encountered from inside.  It would not budge.  Since it was closer to the inside end, I went back inside and put the blockage removal tool on the end of the rod and started adding rods while still using the shop vac from the inside.  I captured the clog and pulled it back to the inside.  It really resisted going around the 2) 90deg. bends, but I got it out in one piece.  It was a hard-packed ball of lint, oval in shape, about 10" long!  Altogether, we removed over 10lbs. of lint from the duct!

After the clog was gone, I used the brush from both ends again to be sure that the entire run was clean.  Now, when the dryer is on, the 3 flapper doors on the outside hood stand straight out, and the dryer runs for a much shorter time!

I am a technician by trade, and have several mechanical hobbies.  I appreciate well-designed tools.  This kit is EXCELLENT!