Product Code: GST9-BUILD

GST-9MOD1: Build Kit


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Questions on how ATF rule affects these products? View ATF Rule Directory

The complete GST-9 MOD1 build kit is everything you need to build a top tier handgun at a production level price. Engineered from the ground up to capitalize on all the strengths of the GLOCK OEM platform, the MOD1 incorporates the most common aftermarket upgrades as standard features. 80% Arms has created a pistol that not only ships staight to your door but also outshoots you every day of the year. 


NOTE: The jig is not included in the build kit. It must be purchased separately.


The MOD1 does NOT accept GLock 17 slides. The frame only accepts Glock 19 and Glock19L slides. Purchase of any MOD1 includes one compact grip module in the same color as the selected frame. No substitutions are possible.


Due to a change in ATF regulations, we cannot legally include the jig or frame rails with the GST-9 MOD1 frame. The jig and frame must be purchased on our website as two separate items. Each jig includes one set of GST-9 frame rails. You will need to purchase one jig for every GST-9 MOD1 frame you plan to build. Frame rails are ONLY included with the jig, not with the 80% pistol frame itself. 


Because the GST-9 MOD1 is not a firearm, in most cases it's currently legal to purchase and own an unfinished frame in California. California law prohibits building an off-roster handgun as well as a home built firearm that does not contain an integral 3.7 oz piece of stainless steel. If you are purchasing a GST-9 MOD that ships to California, you certify that you have a law-enforcement exemption or intend to build and maintain the product outside of the state. 


Features that every MOD1 comes with:

  • GST-9 MOD1 Pistol Frame
  • MOD1 compact grip module 
  • Wraith Slide RMR Cut Slide - Completed
  • G19 Fluted Barrel - Black Nitrided
  • G19 Lower Parts Kit 

Shipping Restrictions: This item is restricted from shipping to New Jersey, New York, Hawaii, Connecticut, Rhode Island, Washington D.C., Maryland, Illinois, California, Washington, Allenspark Colorado , Coal Creek Canyon Colorado , Eldora Colorado , Eldorado Springs Colorado , Gold Hill Colorado , Gunbarrel Colorado , Hygiene Colorado , and Niwot Colorado, and Denver Colorado.