These are umbilical cord scissors: These are PEX cutters: Both are made to cut through tubing, but their forms are obviously quite different.The outer edges of the umbilical cord scissors are rounded, to prevent any accidental injuries. The tool is monomaterial (stainless steel, for ease of sterilization). The two blades slice in a bypass arrangement, for the cleanest and quickest cut. They're used by medical professionals wearing latex gloves, so there's no need to add any grip material to the handles.Note: These are branded with "Breeder's Edge" as this model is used by animal breeders. The PEX cutters are considerably more robust, as PVC is tougher to slice through than human tissue. Because plumbers may be making dozens of cuts in a single session, often a spring is added to reduce fatigue. Only a single blade is used, for the sake of economy; as the blade goes dull, it can be removed and replaced. The jaw of the tool, which features a slot to accommodate the blade, is made wide to allow the PEX to register against the tool; this ensures a perfectly plumb cut, which is important for adding watertight connections to the PEX. While both tools are form follows function, the difference in execution detailing is all to do with the specificity of the applications.