I started cold crashing multiple beers tonight for xmas/new years and unfortunately I only have 2 modified pressure lids for my fermonsters. In the past I would use a mylar balloon with co2 to prevent suck back of oxygen, however this time it dawned on me to use a 2 liter bottle and a carb cap. Purge bottle, add 10psi and hook up to fermenter, easy as can be.
Hands down, these are the most useful little gadgets in my brewhouse. I use them for everything from oxygen free introduction of gelatin finings, oxy free dryhopping in my fermzilla, purging my closed transfer lines before I move from fermenter to keg, making hop water and seltzer, quick carbing dregs and the list goes on.
How do you use carb caps?