The Ergonomic Prym 610950 Tracing Mouse is an accessory from the new prym ergonomics series. The tracing mouse is ideal for marking on all types of fabrics. A fine gear at the top of the tracing wheel in the shape of a mouse leaves a distinct fine line of chalk, which can be easily removed by hand or by washing after sewing the fabric. The mouse has a transparent window to see the chalk level and when it needs refilling. For replacement chalk, you can purchase the white Prym 611886 powder. The mouse also has a cap so you can store it safely. This practical chalk wheel was awarded the Red Dot Design Award, as it ensures precise and fatigue-free work. It is made of plastic and metal and its dimensions are 4.9 x 8.5 centimeters.