Rockwell Multi-Speed 1028 drill press speed reducer. Was made for the Rockwell 14" drill press (DP220) but may fit other drill presses with a 4 speed step pulley and a standard 2 3 /4" steel tube. It fits inside the middle tube and adds a third pulley so you can drill at really low speeds. In general I find that most smaller drill presses are faster than I would like for large drills. This one was designed to reduce the minimum speed of the Rockwell 14" drill press down to 270 rpm. The reducer includes 2 belts in good condition. The pulley has a main cast iron piece that clamps to the outside of he tube and holds the speed reducer pulley captive but allows it to swivel and thus by its cam action tighten/loosen the pulley. The outer screws will also lock the cam action. If I spin the pulley up my hand it will spin for 15 seconds, but I do hear a little bearing rumble noise. $70 + shipping. US sales only.
Link to documentation:
VintageMachinery.org - Delta Manufacturing Co. - Publication Reprints - 1028 & 1029 Multi-Speed Attachments for 14" Drill Press