Design Tools are laser cut from clear 1/8 inch acrylic. These tools were originally created for drawing and/or cutting around and are designed to allow the home machine quilters ability to lay down accurate repeatable design lines, fill, and border designs. Some Low Shank Home Machines can use these tools with the appropriate ruler foot. Be sure your ruler foot cannot hop on top of 3/16 inch acrylic. If this can happen, consider using a thicker acrylic: 3/16 inch acrylic templates (Home Machine Quilting Tools) or 1/4 inch acrylic templates (Machine Quilting Tools).
Nested tools represent great value for the customer. Since each size is contained within another, only cutting time adds to the cost of the tool for the extra sizes.