Product review (5 stars): Lint Cleaner Rotary Dryer Vent Cleaning Kit
This item worked as advertised.  The rods were exactly what I needed to make two 90 degree turns in a ten foot long vent.  The rods were flexible yet stout enough to make the turns and clean the vent while being turned by a cordless drill.  I had tried another kit before this one and the "rod" was just not sturdy enough to force the brush down a ten foot vent while making any turns.