According to 9to5mac, Apple has chosen to to drop “5” from the new iPhone’s name and go entirely with letters.
9to5Mac says that Apple believes the name would be too confusing. It’s also possible that Apple simply thinks it’ll be harder to sell a model with “5” in the name at a time when the iPhone 6 and 6S are around.
The 4 inch iPhone SE will be an iPhone 5s with improved specs. According to 9to5Mac reports that it’ll have an A9 processor, like the iPhone 6S, an improved 8 megapixel camera, like the iPhone 6, as well as a fingerprint scanner for Touch ID and NFC for using Apple Pay.
There be few changes in the body of the phone which includes slightly curved edges along the phone’s glass and a power button off to the right.
Update 27/02/2016 : 9to5mac reports that the Apple event will be held in the week of March 21st instead of March 15th.