Seems they are both labelled A1429. I have a UK A1429 so I guess if you are buying one in the states it will automatically be the CDMA version... otherwise it will be A1428 you would receive for GSM
Seems verizon and sprint models have identical hardware but on the bottom of my box it tells me what bands the phones support and u can figure out what kind of model it is by comparing it to the 3 descriptions at the bottom of this post. I added a photo of my GSM A1429 box saying GSM/EDGE and LTE.. don't see CDMA
In deciding to go with blazing fast LTE capability in the iPhone 5, Apple was forced to release three different devices to meet compatibility with different LTE network standards worldwide.
The A1428 model iPhone 5 is the Canadian and US AT&T network GSM iPhone, including broad support for UMTS/HSPA+DC-HSDPA (frequencies 850, 900, 1900, 2100 MHz), GSM/EDGE (frequencies 850, 900, 1800, 1900 MHz), and LTE bands 4 and 17.
The A1429 iPhone comes in two different flavors, one CDMA and one GSM. The GSM model is designed to support LTE in Asia (including Hong Kong, Japan, Singapore, and South Korea). This GSM iPhone will also work on LTE in Australia, Germany, and the UK on bands 1, 3, and 5.
The CDMA version of model A1429 works on Sprint's and Verizon's LTE networks in the US, along with the KDDI network in Japan on bands 1, 3, 5, 13, and 25. The CDMA version also supports GSM bands, making the CDMA iPhone 5 compatible with GSM networks. However, the CDMA A1429 will not support LTE on GSM networks in the US.
Full specs from Apple:
GSM model A1428: UMTS/HSPA+/DC-HSDPA (850, 900, 1900, 2100 MHz); GSM/EDGE (850, 900, 1800, 1900 MHz); LTE (Bands 4 and 17)
CDMA model A1429: CDMA EV-DO Rev. A and Rev. B (800, 1900, 2100 MHz); UMTS/HSPA+/DC-HSDPA (850, 900, 1900, 2100 MHz); GSM/EDGE (850, 900, 1800, 1900 MHz); LTE (Bands 1, 3, 5, 13, 25)
GSM model A1429: UMTS/HSPA+/DC-HSDPA (850, 900, 1900, 2100 MHz); GSM/EDGE (850, 900, 1800, 1900 MHz); LTE (Bands 1, 3, 5)
http://www.iphonefaq.org/archives/972158