cylindrical connector 3d model

Create a precise CAD-style cylindrical connector (unit mm). Start with cylinder diameter 26 mm, length 30 mm. Subtract inner cylinder diameter 20 mm to make hollow tube. Cut ONE rectangular slot into inner wall: width 6 mm, height 3 mm, depth 12 mm (goes inside, not outside). Subtract central hole diameter 8 mm through entire length for electrical passage. Ensure clean straight tunnel from front to back. No extra shapes, no multiple slots, no threads. Minimal industrial design.