This is the ground tape for the Coleman 3.65m x 3.65m event shelter. When laid out on the ground it forms a 3.65m square with a diagonal to hold the shape in a square. This is invaluable in helping erect the shelter. If you've ever tried erecting the shelter without this you will know all about the frustration of trying to attach the canopy to the frame - it won't be square and you'll be engaged in a 'tug o' war' with the other side. The tape was not supplied with earlier shippings of the shelter so whether you want to buy one as an addition or a replacement, this is it.