-Buffer Tube Milling File (meant to shave down the best of an AR-10 Buffer tube so the charging tackle can clear on some higher/reduced mixtures) I’ve engraved BRN-4 416 lowers to imitate the HK 416 logos. With sufficient passes, a fiber laser can perform deep engraving as well and it https://ghostgunsofficial.com/product/ghost-gunner-3-s/