Re: Do I need the two sided printing accessory part in order to be able to print

Hi

Welcome to the HP Support Community. I'd be happy to assist you with the duplexing or 2-side printing query. 

HP Photosmart 7520 e-All-in-One Printer supports Automatic duplexing. You may refer to "Printing specifications" from here. 

HP Printers - How to Print on Both Sides of the Paper (Duplex) (Mac)

HP Printers - How to Print on Both Sides of the Paper (Windows) (Duplexing) 

Hope this helps! Keep me posted. 

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