As expected from a funnel, this device will help you to pour things into a small opening without spilling anything. It does have one feature that I hadn't considered though! When you pour your beverage into the funnel after setting it in a flask, the lip of the flask forms a seal with the base of the funnel. The funnel will fill without draining through until you slightly raise/tip the funnel (thus breaking the seal). I like this because it allows me to measure how much I'm pouring into the flask. Depending on the occasion, I might not want to fill my flask to full capacity. If that isn't a concern for you, that detail might be an annoyance. If so, just lift the funnel a bit while you're pouring and the beverage will go in without delay.