Create the perfect softball pitcher’s circle — it’s quick and easy. There is no measuring and no need to scribe the circle. Simply attached the Pitcher's Circle Kit cable to your Streamliner chalker and pin the other end to the front center of the pitcher’s rubber. The cable will put your Streamliner in the proper position for a perfect 8-foot radius softball pitching circle (16' diameter). Streamliner 353 or 70 required.