Understanding Turning Tool Holder Labeling:
The labeling for these turning tools describes most characteristics of the tool. Please see the chart below for what each number & letter corresponds to. There may be other labeling (such as NH2 in example) that is still important but doesn’t describe the core characteristics.
The shank can be measured by calipers, or by referencing the chart below given the proper labeling on the tool. Not all shanks are square, they can be rectangular which can be notated by, for example: 1” x 1 1/4".
The inserts sit on the shim / seat and are usually held by a combination of a clamp & insert screw. Information about the inserts used by the turning tool can be found using the labeling & chart below as well as measuring an insert with calipers for thickness and cutting length.