TechInsights’ preliminary teardown of U.S. retail iPhone 18 Pro Max model A3473 identified Qualcomm’s Snapdragon X80 modem, marked SDX80M, and the SDR875 RF transceiver on September 21, 2026. That gives the U.S. Pro Max a different cellular platform from the smaller U.S. iPhone 18 Pro, whose Apple specification listing identifies the C2 modem.
The finding turns the model-level modem split into a concrete hardware identification. It does not, by itself, establish that either platform delivers better cellular performance in every situation.
The teardown identifies the modem in the U.S. Pro Max
The analyzed iPhone 18 Pro Max contains Qualcomm’s Snapdragon X80 modem and SDR875 converged RF transceiver. The X80 is marked SDX80M inside model A3473.
The same teardown identifies Apple’s N1 wireless module, marked 339M00479, and an Apple mmWave antenna module marked 339M00418. The mmWave hardware is relevant to the U.S. model’s cellular design, but its presence alone does not establish a particular real-world speed or reception advantage.
The U.S. iPhone 18 Pro uses Apple C2
Apple’s U.S. specifications page lists the Apple C2 modem for the smaller iPhone 18 Pro. The two same-generation U.S. models therefore use different modem platforms:
| Model | Market and scope | Cellular modem |
| iPhone 18 Pro Max, model A3473 | U.S. retail model analyzed in the teardown | Qualcomm Snapdragon X80, marked SDX80M |
| iPhone 18 Pro | U.S. model listed on Apple’s specifications page | Apple C2 |
Apple says its C2 modem uses 15% less energy than the C1X and supports mmWave 5G. That is an Apple comparison between C2 and C1X, not a direct measurement against the Snapdragon X80 in the U.S. Pro Max.
Other hardware identified in model A3473
The teardown also identifies Apple’s A20 Pro application processor and LPDDR5X memory in the U.S. iPhone 18 Pro Max. Its analyzed NAND configuration is 256 GB.
The separate wireless and antenna components matter because a phone’s cellular system is more than its modem alone. The X80 works alongside the SDR875 transceiver, while Apple’s N1 module and mmWave antenna are also part of the hardware identified in this particular device.
What the performance comparison shows
A preliminary comparison measured 320 Mbps download and 96.9 Mbps upload on the C2-equipped iPhone 18 Pro. The X80-equipped U.S. iPhone 18 Pro Max measured 343 Mbps download and 45.8 Mbps upload in the same comparison.
In that observation, the X80 device recorded the higher download figure, while the C2 device recorded the higher upload figure. The results came from a single comparison without a documented carrier, location, or controlled methodology, so they do not establish a universal winner between the two modems.
Why Apple uses Qualcomm in the U.S. Pro Max
Apple has not publicly explained why the U.S. iPhone 18 Pro Max uses Qualcomm’s Snapdragon X80 while the smaller U.S. iPhone 18 Pro uses Apple’s C2. The hardware distinction is established for the analyzed A3473, but the reason for Apple’s choice remains unstated.
