Jo Jan offesr three different nock receivers which are available in all models of both multi-fletchers and mono-fletchers. All nock receivers are interchangeable and can be used on any model of the Multi-Fletcher and Mono-Fletcher.

F-51 (cock feather out)
3-fletch (spacing in degrees) 120 - 120 - 120
4-fletch (spacing in degrees) 75 - 105 - 75 - 105

F-71 (cock feather down)
3-fletch (spacing in degrees) 120 - 120 - 120
4-fletch (spacing in degrees) 90 - 90 - 90 - 90

F-81 (Nock Receiver for Crossbow Bolts)
3-fletch (spacing in degrees) 120 - 120 - 120
Fletches arrow sizes 2219 and 2117