A textured surface on a handle or a floor-contact accessory can look like a cosmetic finishing touch. In manufacturing terms, it's a specified property — friction — engineered deliberately, the same way resistance rating or webbing denier are specified elsewhere in a product line.
Friction as a specified property. The coefficient of friction between two surfaces — how resistant they are to sliding against each other — is a measurable, controllable property, not an incidental side effect of a material choice. When a manufacturer adds texture or a rubberized coating specifically to improve grip, they're targeting that coefficient directly, independent of the component's other properties like weight, flexibility, or load rating.
How texture patterns achieve this. The most common approach molds a raised pattern — grooves, dots, a cross-hatch grid — directly into the surface of rubber or foam during production. This is conceptually the same idea as knurling, the raised-ridge pattern cut or rolled into metal tool handles, which we covered in our bar-attachment piece. The mechanism is identical (a textured surface increases effective friction over a smooth one); only the material and manufacturing method differ between a molded soft-goods texture and machined metal knurling.
Why durometer varies by contact type within the same kit. Durometer measures a rubber or foam compound's hardness. A single kit often uses more than one durometer across different components, deliberately: a floor-contact anchor or foot plate frequently uses a harder compound at its traction surface, because grip against a hard floor benefits from a firmer material that resists compressing and losing its texture pattern under body weight, while a hand-contact grip elsewhere in the same kit uses a softer, more compressible foam because comfort and even pressure distribution (covered in our handle-diameter piece) matter more there than raw hardness.
Why this is a deliberate spec, not a default finish. None of these choices happen automatically during manufacturing. Selecting a texture pattern, a coating type, and a durometer appropriate to each specific contact surface requires treating friction as its own engineering target, evaluated separately for each component based on what it actually touches during use.
The takeaway. A non-slip surface is a specified, engineered property — achieved through texture patterns conceptually related to metal knurling, and tuned through durometer selection appropriate to each contact point in a kit. It's a small detail, but like the rest of the components covered in this series, it's the product of a deliberate manufacturing decision rather than an afterthought.