I would trust parts from this source:
BN - AR-15 Lower Build Kit W/ Enhanced Oversized Trigger Guard - M4 Stock
BEAR NECESSITIES - AR-15 LOWER BUILD KIT WITH ENHANCED ALUMINUM TRIGGER GUARD - M4 STOCK: This AR Lower Parts Build Kit comes with a Bare Necessities complete LPK and a Tactical Sport Mil-Spec M4 Stock Kit. This lower build kit comes with everything that you need to complete your 80 percent...
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