There are a few things to consider when freezing a hide. First, like the other response, good heavy plastic bags are important to keep them from freezer burning. Second, the freezer is just slowing down the bacteria, but it is still there. It is best to keep the hair outside, rather than inside out. The hair acts as an barrier keeping moisture from escaping. I've found that a good double layered heavy black colored garbage bag rapped tightly around a hair-out hide, can last up to two years. Fleshing, salting and pickling them first will prolong freezer time. The less blood you have with your hide the better. Blood spots are difficult to tan because of the bacteria decaying the hide (skin.) The first areas to go bad are the ears and face, thinner skinned areas. Hope this helps.