Kythera SA Main Sear Switchboards the longer castle nut on

the longer castle nut on the G28 interferes with the closing of the stock rail when the CO2 insert is being used instead of a 2

the inserts have more uses than just being paired with one of these stocks

weight and feel of a real single-action firearm trigger

This trigger mount is compatible with all generations of the V2 Fusion Engine from the very original to current production

Kythera SA Main Sear Switchboards the longer castle nut onYou want to try doing a fancy trigger job but don't want to take a chance of messing up your only sear? Pick up a spare! Original main sear used with all Kythera SA models. 4140 steel, gas nitride case hardened.