6 flutes, straight shank, alloy tool steel. installed in the lathe for cutting metal tools. Straight flute hand reamers has been used in ferrous metals and most non-ferrous metals. The reamers is precision ground with straight flutes to produce smooth, accurate holes while delivering long tool life. more spacious for reaming holes are drilled after processing (or reaming) on the workpiece, mainly improving the precision of the hole, reducing its roughness, finishing and semi-finishing tool for the hole. colour:Silver gray Material:HSS size:4/5/6/8/10mm Package Contents: 20 *Hand Reamer Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.