It really depends on the height of your freezer and where the compressor hump is located. The hump on mine takes up about 50% of the overall floor area of the freezer, so the collar was a must. I can't remember right now, but I believe that my kegs, with disconnects (pin lock) are about 27ish inches. I have an 8 inch collar that I attached to the lid which gives it plenty of room. Ball lock kegs have different dimensions, though.