iPhone SE (Special Edition) models are nearly identical in appearance to the iPhone 5s, apart from matte-chamfered edges rather than shiny ones, but have many innards more in common with the higher performance iPhone 6s.
All iPhone SE models are powered by a 1.8 GHz 64-bit "Apple A9" processor and have 2 GB of LPDDR4 RAM and 16 GB, 32 GB, 64 GB, or 128 GB of flash storage. They also support 4G/LTE, 802.11ac Wi-Fi, Bluetooth 4.2, and NFC (for Apple Pay), have a bottom-mounted headphone jack and use the "Lightning" connector to hook up with a Mac, PC, dock, or power adapter.