Plain Swivel Cutter nº444, Cs.Osborne.

The opening knife, also called swivel or swivel knife, allows you to incise the leather to give relief to your pattern (leather pushing). The index finger is positioned on the stirrup, the thumb and middle finger on each side of the handle as if holding a pencil. The index finger controls the depth of the cut while the other fingers are used to rotate the tool to make the desired shapes. The incision of the leather with the pivoting knife is done before the pushing work.
This plain swivel cutter is furnished with medium blade Osborne #446-B 2(3/8″ only). Chrome plated. Hardened tool steel blade.