A junction box built around the Wago 221 lever connector — the orange-levered clamps electricians love. Pick your connector series (221-4xx for wire up to 4mm², 221-6xx up to 6mm²) and size (2, 3 or 5-way), and the box cuts each bay 0.2mm proud of the real clamp body — 18.8mm for a 221-413 — so connectors click in under their retaining lips and stay put. The screw-on lid drops a 1.6mm rim into the box with 0.1mm of clearance per side. Clamp count sets how many connectors sit side by side (1–6). Cable diameter is the one to measure: it sizes the reinforced entry holes (cable + 2mm of clearance) and tells the box how tall it needs to be. Every bottom cable gets its own zip-tie anchor inside, so a tug on the cord pulls on the tie, not the levers. Set the wall-mount screw diameter to 0 if you'd rather not have mounting holes in the floor. Print tip: both pieces print as-is with no supports — box open-side-up, lid face-down. PETG with 3 perimeters takes M3 screws straight into the 2.8mm corner pilots. And the obligatory word of caution: this is a tidy enclosure for low-voltage, lab and hobby wiring — it is NOT a certified electrical enclosure, so in-wall mains work belongs in a code-rated box. Clean-room rebuild from the connector dimension table; inspired by the Wago 221 junction box generator on MakerWorld (model 591912, CC BY-SA).