We used about 175 bags, did not have enough of the right size and had to buy extra off of ebay - came up with special Nascar bags, which was perfect because the quilt was for a friend who is a Nascar fan... I used my 4x12 ruler to make sure that the square was centered around the logo and cut out front and back at the same time. It felt like I was cutting bags for almost all of last summer. Here is another view.