Four blades with holders ( 2 for bottom and 2 for top ) are ready to use in MR11 and MRS11 dough roller sheeter. Blades are made from high density natural HDPE plastic approved by FDA. Thickness is 0.25". Size of blades: 10"x2", 10"x4.25", 20"x2", 20"x2". Holders made from solid aluminum square bar and has aluminum posts for springs. One side of holders has hole for screw 3/8"x16 and second side of holder has pin for hole 0.375" in wall of machine. Blades connected to holders with stainless steel screws and nuts.