This is the second Chill Sack that I have purchased. The first was for a Christmas present for a hard to buy for 22-year-old young man. He loved it! The larger size can actually fit 2 people very comfortably! I purchased this size because I wanted one for kids to sit on and save my furniture from their constant flopping! I needed a size that is more manageable for me to move. The larger size is a bit difficult to move around. This sack arrives in a box and in that box is a very hard square block of material. You have to unzip that bag and take out the block to put into the cover it goes into. This is very easy to do. You seem a bit worried that it will ever fit the cover that you put it in, but it does! This particular size and the larger one is very heavy so if you cannot lift more than 50 lbs, you will need help. At first, you cannot imagine that this will expand and become the more comfortable thing ever, but give it a couple of days of flipping and fluffing and it will be perfect. You can reshape it in whatever way you want to sit. Our family laughed as we watched it grow and grow! Worth every penny and will save your other furniture! I will probably buy one for each of my kids for Christmas so they don't fight over this one.