The Excalibur Proflight is constructed using the highest quality carbon fiber with .001" straightness and +/- 1 grain weight tolerances, the Excalibur Proflight Carbon Bolt will ensure repeatable accuracy which is everything for confidence and success. The Proflight arrows are standard equipment on the Assassin 420 TD and the Bulldog 440. FeaturesHigh quality carbon fibre.001a ^2 straightness tolerance+/-1 grain weight tolerance2a ^2 Blazer vane with a 3 degree offset for optimal arrow flightWhite cresting allows for easy shot placement verificationConsistent arrow flight