My favorite type of ruler is by Creative Grids. They are clear with black markings and have non-slip discs on the back that really work. I find myself using the 6 1/2 x 24 size most often. They make a variety of sizes, and I am replacing all of my other rulers with these. If you can't locate them at a quilt shop, their website is: creativegridsusa.com. I have not tried to contact this website - just copied it off the ruler. I highly recommend these rulers to all quilters!