Tenpoint HEA7793 CenterPunch HPX Alpha Blaze Carbon 20" .001 Straightness RedSuper bright for superior flight visibility, the lighted CenterPunch HPX is equipped with TenPoints Alpha Blaze HPX Lighted Nock with easy activation and deactivation. Upon firing the crossbow, the bow string pushes the nock fully into the bushing and activates the LED Light. To deactivate, grip the nock and pull straight out with your fingers or Bednar Perfect Puller (sold separately) until the LED Light turns off. LED Light lasts approximately 24