For personal kitchen use. Preferably from Amazon.
I found this to be effective. It is also fairly cheap. You may want to look for it in a hardware store rather than pay the Amazon shipping charge.
I agree with @LostInParadise‘s recommendation. They work great! You can also find them at The Dollar Store for $1. They’re called Zip – It or UnClog – It.
I have a 25 footer but it comes up a little short. Sometimes you have to snake the drain from the vent on top of the house.