I need a 3D-ready STL model for a screw-on bottle cap that incorporates a twist-to-open dispensing feature. The cap will be manufactured in plastic, so wall thicknesses, undercuts, and overall geometry must respect common injection-molding constraints while remaining printable on an FDM or SLA printer for prototyping. Your task is to translate the concept into a clean, watertight CAD file, then export the final STL. Feel free to work in SolidWorks, Fusion 360, Inventor, or any comparable parametric package—as long as the STL comes out error-free and dimensionally consistent. Deliverables • Native CAD file with editable history • Production-ready STL (0.15 mm tolerance or better) • Simple drawing or PDF noting key dimensions, thread specs, and the twist mechanism’s travel/stop points I’ll provide bottle neck dimensions as soon as we start so you can match the threads precisely. A short video or set of screenshots showing the dispense action would be a bonus but isn’t mandatory. If you’ve designed consumer packaging closures before, that’s a plus—please share a sample.