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These flats have the top rails bent, but the the die we used to do the step went bad and now we are offering them up at a discounted price.
THESE FLATS DO NOT COME WITH RAILS!!
We have B1-11, B1-71, B2-21, B2-41, B2-51, and B2-61 flats ready to ship.
To use these flats you will need to have a 5mm and 7mm reamer. The physics of bending sheet metal make it next to impossible to have a bend close to a hole without distorting. To solve this the holes on the flat are undersized and need to be reamed to size after bending. Look at the receiver flat instruction page to see more info.
This item is made in the United States and counts as a 922r compliant part.