Find the center of any irregular object --- This transparent center finder compass can draw circles and find the center point of irregularly shaped or rough objects up to 200mm/7.9" in diameter. Versatile Centering Tool --- This centering tool has different diameter holes ranging from 10mm (0.4 inch) to 150mm (6.0 inch) radius. It can be applied anywhere a hoop is needed, suitable for woodworking, arts, crafts, school projects and wood finishing; suitable for wood, poster board, plastic, metal, glass, composite materials and more. CLEAR CIRCLE DESIGN - Clear aryl with clear index helps you place quickly and easily, you can easily find the largest circle on the log, avoid unnecessary waste of wooden wedges, and achieve maximum yield. High Quality --- Using high quality transparent acrylic material, the product is eco-friendly and durable, with good light transmittance and high clarity. EASY TO USE --- Simply press a small nail or pin (not included) into the center hole, insert a pencil into the diameter hole of your choice and rotate around the center point to make a circular mark.