http://pastport.jp/user/mikehouke/timeline/Economy%20Planetary%20Geared%20Stepper%20Motor https://www.oyostepper.com/category-26-b0-Geared-Stepper-Motor.html .This Nema 17 stepper motor with 48mm body and 1.68A rated current, integrated a planetary gearbox of 50.9:1 gear ratio. ja-JP