The model of this device RM-1116 which indicates that it is the Unlocked Dual-Sim (as stated in the title of the listing) and is therefore an international model. Dual Sim model is Cat 4 LTE. The only other model of Lumia 950 XL is the RM-1085 which is a Single Sim model. (Also an international model) Single Sim models is CAT 6 LTE.
The item "Factory Unlocked Dual-Sim Microsoft Lumia 950XL Black with Display Dock Bundle" is in sale since Friday, January 15, 2016. This item is in the category "Cell Phones & Accessories\Cell Phones & Smartphones". The seller is "socrfan531" and is located in Austin, Texas. This item can be shipped to United States.