They are generally referenced by a letter which equates to a size range. The disposable blades slide along a tapered groove. Igor Tokar. Sincerely.
Engine Valve Guide hand Reamers - from 4.47 to 11.02 mm spiral flute
8.84 Engine Valve Guide hand Reamers
8.95 Engine Valve Guide hand Reamers HSS
9.52 Engine Valve Guide hand Reamers HSS
9.54 Engine Valve Guide hand Reamers HSS
9.56 Engine Valve Guide hand Reamers HSS