Early Colt MP marked bolts. These are parkerized. They are not marked with a C.
Would be correct for a mid 60's to early 70's XM177/SP1/M16A1 etc build.
One has the original 4 coil extractor spring and it is $65 to you.
The other has a newer spring with a blue insert on the extractor. $50 to you.
Both are used.
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