My rotary blades kept getting dull fast and I assumed it was due to all the cuts in my cutting mat. I found I had better results using my rotating mat which has a mat that heals itself so went looking for one of those. Searching on the web for one large enough to cover my entire table was difficult. So I ordered one 4 x 8 and made the table to fit the mat. This one has markings on both sides........one side is green and the other side is black. Can't remember where I got it from but I'm happy with it. My blades last much longer now. Had looked for what is called "rhino" something or another and the site I purchased mine offered those too but was told they were better for shop work and not quilting work.