Product review (5 stars): Exactly what I needed
We have a Maytag 3000 series dryer that started making intermittent squeaking noises during operation.  It gradually grew to become constant.  After reading up on several Google search results, I found that the most likely culprits were worn out rollers and the idler pulley.  That's everything in this kit, plus a new belt and a good supply of those little weirdo nylon triangular-shaped retaning clips.

The whole job took me around an hour.  Even though the existing belt looks to still be in good condition, I went ahead and replaced it for good measure and vacuumed all the lint that had piled up over the years.  Put the whole thing back together, and ran a short empty cycle as a test.  Now it runs whisper-quiet like it did when we first had to delivered --  music to my ears.