Product review (3 stars): No instructions, but it worked.
Here is how I repaired an old, leaky garbage disposal.

1. Removed old plate by unscrewing two screws.

2. Removed and threw away old plastic pipe and rubber gasket.  Scraped gak & other deposits from area of garbage disposal that will meet the new gasket.

3. Brought pan of water to simmer and then turned off heat.  Stood the flange-end of the new white pipe in the water for 5 minutes.

4. Forced new metal plate over softened plastic flange.

5. Put new, black gasket on white, plastic flange.  There is a groove on the inside of the gasket, mid-way down.  It fits over the white, plastic flange.  One end of the black gasket has a bit of a "lip" to it -- I pointed this toward the "flex" portion of the white, plastic pipe.

6. Used the old screws to tighten new, metal plate to old garbage disposal.  The new gasket sealed into the recessed space on the garbage disposer well.

7. Bent "flex" region of white, plastic pipe so the non-flange end inserted into drain-pipe.  Tightened screw-cap of drain pipe to seal-in the white, plastic pipe.

Good luck!  :)