The Challenge Grifo Open tire combines a tried and true tread pattern with the versatility and ease of use of a clincher that’s perfect for racing and training. At 300 threads per inch this tire is remarkably supple for a clincher. Low profile knobs are great on fast grass courses and hard packed graveldirt but aggressive enough for mud. If you could only have one clincher for the entire season the Challenge Grifo would be a great choice.