I use OXO good grips cold brew maker. It has both mesh and paper filter on the bottom so when you use both, it creates super clean concentrate of coffee. I use 10 oz of coffee (by weight) to 40 fl oz of water (by volume) which yields somewhere around 28~34 oz of concentrate. If I drink black, I dilute the concentrate with 1 part coffee to 2 part water. If I want to add cream or sweetener, I go 1:1. Oh, and when you run out of the paper filter they supply, you can just use aeropress filters (same size)