end mill holder
NMTB page 288
NMTB End Mill Holders are designed to fit milling machines using the National Machine Tool Builders (NMTB) spindle taper of 3-1/2" per foot, with manual or power draw bar. All holders are hardened and precision ground to ensure accurate size and concentricity. They will hold single or double end mills, except where noted. Set screws are furnished and are located according to Weldon Shank specifications.

R-8 page 288
R-8 End Mill Holders are designed to fit Bridgeport and other milling machines using the R-8 spindle taper. All holders are hardened and precision ground to ensure accurate size and concentricity. They will hold single or double end mills, except where noted. Set screws are furnished and are located according to Weldon Shank specifications.