Sylvan Arms Gen. 3 1-3/16-16 Folding Stock Adapter for AR-15 Style Rifle - ARH300
https://palmettostatearmory.com/syl...ock-adapter-for-ar-15-style-rifle-arh100.html
https://palmettostatearmory.com/syl...ock-adapter-for-ar-15-style-rifle-arh100.html