If you live in an area where there are rolling hills, we highly recommend purchasing a 7 speed or a 21 speed.
We don't recommend the 3 speed because it does not have a wide enough gear ratio to get you down to a real low gear to get you to the top of the hill.
The 7 speed will be good for rolling hills that are not too steep and long, if you are recovering from an accident or want a decent exercise going up hills, 7 speed will be great.
The 21 speed is about the same as 7 speed but the 21 speed will get you to an even lower gear to get you up any kind of hill you will be facing, 21 speed low gear will get you up any kind of heavy-duty hill with confidence.
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