Safety Key for WalkingPad® Treadmills

Looks very nice. Easy to put together. I've only had it a few days. So I will come back later to give my review. I did notice a warning sign on it. It says fo ages 18 to 60. I'm 69, so now I'm confused. Didn't notice an age limit when I purchased it. Is there a reason this walking pad has an age limit up to 60?

I kept loosing the cable to ordered two more. Arrived in good time

Only ordered safety key, was only $5 which is a good deal. This was small enough to fit in a ring box but had a $30 shipping charge. Seems like a little extreme if you ask me.