N7289 case:ball BALL BEARING,1.3812" ID x 2.8322" OD x 0.94"

Niagara Cutter N7289 High-Speed Steel End Mill, General Purpose, Regular Length Keyway Tolerance, TiAlN Coated, 2 Flutes, Square End, 1-1/2" Cutting Length, 13/16" Cutting Diameter
Keyway tolerance end mills have a negative cutting diameter tolerance that allows more control over the size of the cut than conventional end mills || Two flutes offer better chip-carrying capacity than end mills with more flutes, enhancing the tool's ability to remove material || Titanium aluminum nitride (TiAlN) coating lubricates the end mill for high-temperature stability and abrasion resistance at high cutting speeds, offering better heat resistance than TiN and TiCN coatings || High-speed steel is compatible with a variety of materials || Square nose end mills (also called square end) create sharp, unrounded cuts