The 74161 is a replacement scraper profile for Modeler’s Knife PRO, rather than a complete knife. The exact Tamiya reference describes a 7 mm-wide and 2 mm-deep working profile for reshaping plastic parts with light pull scraping. The selected listing separately gives 0.5 mm blade thickness; those are different dimensions, not conflicting depth limits.
Two replacement blades are stated in the retail response, and the maker describes a two-blade package with a plastic case. A receiving handle is not part of the replacement-blade package. Confirm the Modeler’s Knife PRO system instead of assuming every Tamiya or generic hobby-knife chuck takes this scraper.
Choose this wider scraping profile when it adds an operation to the PRO handle you already use. GodHand’s BBH set instead supplies narrower 1–3 mm flat chisel profiles with a common 3 mm shank and a different attachment interface. The complete Tamiya 74098 PRO knife is the relevant complete-tool option if you still need the handle, but its normal mixed blade inventory does not establish that 74161 scrapers are supplied in that separate kit.