High performance Designed For micro applications. Micro machining applications involve miniature tooling that requires very high attention to tolerances and detail in their construction. These end mills incorporate 30 degree helix and Altin coating to insure a high degree of precision. Miniature end mills also routinely require RPM in excess of 40, 000 RPM or more so attention to both RPM capacity and accurate chip-loads is mandatory. Choose 2 flute end mills for efficient vertical plunging, pocketing and slotting operations. 4 fluted tools offer the promise of improved surface finishes, longer service life and increased feed-rates with peripheral milling applications, #51661, direction Up-cut, (D) diameter 0.015, (b) Cutting height 0.045, (D) shank 1/8, overall length (L) 1-1/2, Type Square end, flutes 2, 51661 Altin coated CNC steel, stainless steel & composite square mini end mill 0.015 dia x 0.045 x 1/8 shank