I hated my 1st rotating mat as it wouldn't stay on the bottom section when I turned it. Then at a quilt retreat I was at, I saw a round round that seemed to work great by Martelli. It also comes with a pressing mat. But of course Martelli is a bit expensive but just after getting home from the retreat, Martelli was having a sale so I jumped on getting that mat then. It's round, 16.5" across with a square marked in the center with increments of 1.0" up to 10.0". Very well made and I love it. So glad I got it when I did. Fairly lite weight too.