This product was my first-time QVC purchase. There are a couple other places you can purchase this but for a long time you used to only be able to get it on QVC so that’s where I bought mine. Since then they have also come up with a new package with more to it than the 2 rulers that I have. This is a great tool for the perfectionist or for those that have a hard time “eyeballing” when matting your pictures. To mat a photo (or add a border) you first adhere your photo to the paper leaving room around the edges. The nice thing is that this can be an odd-shaped scrap paper. Next, chose the size of mat that you want and line up the ruler. There is a lip on the ruler so it will catch when you butt it up against your photo. Take the exacto knife and cut along the ruler. Continue on all sides for the perfect mat. This can be done multiple times for multiple mats and layering. The mat that comes with the Perfect Layers is self-healing but you can use any exacto knife and self-healing mat. I prefer a larger 12×12 one that I use. The only trick to using this system is to be careful with the knife – so you don’t cut yourself or take a chunk out of the plastic ruler.