"New Archery Products Spitfire Maxx Mechanical Broadhead has a legendary design with a razor-sharp cut-on-contact tip section for even greater penetration. Micro-grooved ferrule slices cleanly into tissue as the triple .030"" thick blades open instantly to widen the cutting path. Unique hassle-free design requires no O-rings to seal the blades. Cutting diameter: 1-3/4"". Manufacturer model #: 60-665."