An ultimate light-weight hunting arrow featuring Carbon Express backbone technology which integrates thin strands of Kevlar into the weave for added strength and impeccable 360 degree consistent spine. Paired with famous Red Zone Technology and you have a deadly recipe for unmatched broadhead accuracy. Straightness factor: .0025". Weight: 150 (6.6gpi), 250 (7.5gpi), 350 (8.4gpi). Weight tolerance: 1 grain.