As you remember, Apple began upgrading the entire iPhone 6S and SE lineup with double the amount of memory for free. So for some of those phones left over with 16GB or 64GB configurations that have been returned or opened, Apple is going to sell them as refurbished devices with a full-year warranty as well. The prices are about $100 to $110 cheaper than their sealed-in-the-box counterparts. While the new 32GB iPhone 6S and 6S Plus run for $549 and $649, the refurbished models (though with only 16GB) run for $449 and $529, all respectively. We'd stray away from buying any phone with only...
Source: http://www.gsmarena.com/apple_begins_selling_refurbished_iphones_for_up_to_100_less-news-21530.php