The largest of the Alabama groundsheets designed for the size 3. You could use it with the size 1 or size 2 but then there would be bits sticking out the ends. I suppose you could prop open one end and put some welcome mats out for people to wipe their muddy boots and to protect the ground (we're big fans of protecting the ground btw) where everyone comes in and out but in the main we think the size 3 groundsheet matches the size 3 tent quite well. Unless you're a tent rebel. Made from 450g/m2 polyester coated fabric.