Is it okay to put two of the same item on your registry? For example: I put two bedding sets because…

Is it okay to put two of the same item on your registry? For example: I put two bedding sets because I like them both and it wouldn't matter which one I received. Is this okay to do or should I only put one of each item on my registry?

And is there anything I will absolutely need that I should add on to it? I'm a FTM and have no idea what is necessary and what isn't. HELP!