When I received it from Dr. He showed me that it was enough snow to be buried and that the maximum amount when buried was this much. When I told him that I had been recommended an opening at another hospital, he said that I didn't need to get an opening. Looking at other reviews, it doesn't seem like people recommend openings a lot. I asked if there were any more questions and left! What's disappointing is that they don't tell you what line you're currently holding. I didn't ask because I forgot...