I have a brand new, Yankee Hill Machine Diamond Specter Upper receiver. I have both 1/9 and 1/7 twist rates. This is a top quality mil-spec product, and no expense was spared in making this upper. The barrel is diamond fluted, free floating and chrome lined. It has M4 feed ramps. You will not be disappointed.

For $140 more, I can include the mil-spec bolt carrier group and charging handle.

Thanks

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