When I went to register my Beretta Nano pistol on-line, the product description stated that the pistol has one 6 round and one 8 round magazine. My pistol came with two 6 round magazines.

Nano Magazines

The product description that you viewed is the internally-assigned Beretta description for the product in its final configuration.  All Nano pistols produced prior to 1 December 2012 were shipped with two 6 round magazines.  This is the proper packaging configuration for this product.  Nano pistols manufactured on 1 December 2012 and later, will incorporate a configuration change incorporating one 6 round and one 8 round magazine.  For those that desire to have an 8 round magazine for their Nano, they can be purchased as an accessory from Beretta.   We will also be offering a 6 to 8 round extension kit to convert your 6 round magazines to an 8 round capacity.