nsr 4dSteel 1.000″ x 6″ Square Shank Tool Holder to hold a NG 4R (Rht Hand) No Coolant. In stock. NSR 164D NSR is desned to elevate the radix (nose bridge), refine nostril width, enhance tip projection, and achieve an optimal length-to-heht ratio. This innovative technique yields striking yet naturally appearing results, seamlessly