The LineJammer® Pro, the best-spined and weight shaft in its class, gets even stronger and better with the addition of our exclusive Diamond Weave technology. The high-performance LineJammer® Pro is competitionproven and offers maximum diameter line-cutting ability for ASA and IBO competition. Features the BullDog™ nock collar for added strength and protection. Spine-selected for a consistent matched set. GrainsPerInch:7.0 | Spine:0.358" | Diameter:0.381"