After all of your bottles have been safely filled and corked, you can choose to put capsules over the neck of the bottle. While not necessary to preserve the wine, they give a nice finished look to your bottles, and when coordinated with labels give your wine a professional look. Capsules are often called shrink-caps, because heat is used to shrink the plastic onto the bottle neck, holding it tightly and smoothing out any wrinkles or seams in the plastic. These can be applied using a pan of boiling water or a heat gun like those used to strip paint.
