This is the classic and reliable Swann Morton Scalpel handle, size 3. It will fit the ever-useful size 10A scalpel blade that so many use.
It has been covered in a hard-wearing upholstery cord to give it a comfortable handle to hold.
If you use one of these on a regular basis, you will appreciate the discomfort that can come from the metal handle with repetitive work, especially in leather and paper work. This handle cover is both hard wearing and comfortable at the same time.
It also looks super smart!