Nice choice! The minute you ride in water, mud, snow or even small pebbles, you'll be glad you got the fenders. Those really wide and knobby tires displace matter a LOT more than any regular bike tire. I remember going through water at good speed without any fenders; the front wheel actually propelled a stream of water straight up a few feet in the air! guess who drank dirty water a second later?
And the rear one is a life saver for the bike, your back and strangely enough, your bottom. I can home once without a fender once again and my butt was drenched, much worse than my back.
Assembly is easy and you will get a multi-tool gizmo that is enough to assemble the bike and tighten all screws around the bike (good thing to do for safety in case something left the factory not tight enough.
And before I forget, some screws must be left alone though, like the ones on the derailleur. The top 3 here are adjustment screws
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