.22 Caliber Sear Trip Kit for CMMG .22 Conversions and Uppers


FosTecH’s .22 Caliber Auto Sear Trip Kit for the Echo AR-II Trigger or Echo Sport Trigger:

Out of stock


FosTecH’s .22 Caliber Auto Sear Trip Kit for the Echo AR-II Trigger or Echo Sport Trigger:


  • Auto Trip
  • Anti Bounce Weight
  • Additional AR II Trigger Lock Spring

Though FosTecH is confident that the .22 Caliber Auto Sear Trip Kit will work in a variety of different.22 conversions it has only been tested with the products from CMMG and the ones offered on this site. This kit does NOT make your .22 conversion fully automatic. This sear trip kit is designed for you to use the Echo AR-II Trigger or Echo Sport with your .22 conversion. If you have any questions, please see the video at echoquestions.com. The Auto Sear Trip Kit is designed to work in conjunction with a .22 conversion kit or dedicated upper. Please note that the .22 conversion kits and dedicated uppers that are purchased from FosTecH will include an Extra Power Recoil Spring. If the conversion kit or upper is not purchased from Fostech, then an Extra Power Recoil Spring is recommended.

Additional information


300 BLK, 5.56, 6.5 Grendal

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