与同一表的多对多关系(Ruby on Rails)

I'm working on a Rails app that has a "products" model. I want to be able to relate products to each other. Example: product 1 related to product 2, product 3, and vice versa. How would I accomplish this in Rails? I was thinking a join table, but since I'm using the same table as the point-of-relationship I'm not sure how that would work.I'm working on a Rails app that has a "products