831.287620 and 831-287728 models are approx the same model.

Manual for

831-287728 is available, so you can read it.

click the link below:---

http://www.managemylife.com/mmh/owner_manuals/12727/LIFESTYLER-Cardiofit-99020142?brand_name_search=831-287728

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Also to know about how to operate the lifestyler cardiofit.Click this link below:---

http://www.livestrong.com/article/424651-how-to-use-a-lifestyler-cardio-plus-machine/

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