Addressing the common issues of plastic bottle caps being prone to slipping and requiring significant effort to open—especially when hands are wet or damp—this design ensures effortless, secure operation.

1. The octagonal outer ring features slightly curved edges that increase friction, making it easier to apply force and twist the cap open.

2. The 3D‑printed plastic material—such as PLA—is lightweight yet highly non‑slip, offering a comfortable grip.

Toothed Grooves: A densely packed, ring‑shaped array of fine serrations precisely matches the textured edge of the cola bottle cap,

leveraging mechanical interlocking between the grooves and the cap’s edge to transmit torque, allowing users to effortlessly unscrew the cap without it slipping or rotating out of place.