The amazing patent pending Nockturnal lighted nock is a breakthrough design that is more affordable and lighter in weight than most other lighted nocks. The Nockturnal has a string activated "hidden linear switch" that is protected deep within the nock and will not turn on or off inadvertently. It has a speed saving ultra-light design -- other lighted nocks weigh up to twice as much. Battery lasts over 20 hours.
Nockturnal-S: Fits most "standard size" carbon hunting arrows such as Beman ICS, Easton, Carbon Express, PSE, Carbon Tech, Victory, Carbon Impact & most other arrows including aluminum arrows with a super-UNI bushing.
Nockturnal-H: Fits ST Epic, ST Excel.
Nockturnal-X: Fits slim arrows with half outs or hidden inserts such as Easton Axis and Full Metal Jacket, Beman MFX, Trophy Ridge, Carbon Impact HOT, and Easton ACC with X-UNI bushing.