A notching machine removes a defined notch — typically a corner cut — in a single stroke, while a nibbling machine removes material progressively through a series of small overlapping punches to cut irregular shapes. Both are captured within 846249, but the distinction may matter for end-use documentation, technical specifications in purchase contracts, and accurate commercial invoice descriptions.

Not necessarily. A programmable backstop that positions the workpiece but does not direct the machine's punching motion through coded numerical data may not meet the definition of numerically controlled. However, if the controller sequences multiple axes of movement via numerical input, reclassification into 846242 could apply. Importers modifying or upgrading machines should reassess classification before the next entry.