Carbon Express Maxima RED 4mm Arrows 400 Spine 6 Pieces Black. Its RED Zone with Tri-Spine Technology manages dynamic spine through the shot cycle for faster recovery and cleaner steering. The 4mm profile helps reduce wind drift and supports deeper penetration while 360 degree spine consistency promotes uniform shaft-to-shaft performance. Straightness is rated to +/- 0.002 inches max with a +/- 1.0 grains weight tolerance for repeatable accuracy. Specifications for Carbon Express Maxima RED 4mm Arrows: Manufacturer: Carbon Express Color: Black Fabric/Material: Carbon Quantity: 6 Shaft Length: 32 in Diameter: 4 mm Spine: 400 Features of Carbon Express Maxima Red 4mm Arrows: 4mm Micro-Diameter Arrow Shaft Red Zone With Tri-Spine Technology Manages Dynamic Spine Through The Shot Cycle Faster Arrow Recovery Cleaner Broadhead Steering Reduced Wind Drift Enhanced Penetration 360 Degree Spine Consistency For Uniform Shaft Behavior Straightness: +/- 0.002 Inches Max Average Straightness: +/- 0.001 Inches Weight Tolerance: +/- 1.0 Grains Components: Bohning Alpha VanesBulldog Nock Collars4mm Aluminum 50 Gr Outserts Package Contents: Carbon Express Maxima RED 4mm Arrows Carbon Express CX05753: Maxima RED 4mm Arrows 400 Spine 6 Pieces Black