The firm is calling this an "extended" version of the iPhone 5S, writing in a new note that it will be released in the first quarter of 2016.
The note doesn't elaborate much, but there are two key takeaways: The iPhone 6C will likely have a 4-inch screen and will come with a strong metal casing.
Jefferies also thinks the design of the iPhone 6C will be consistent with Apple's previous iPhones, writing the following:
Although iPhone6C is designed as an extended version, it still uses metal casing based on Apple style. We believe that Apple remains consistent in its design. As we have discussed previously, Apple continues to develop increased hardness for the iPhone metal casing, which requires a more complicated CNC and anodized process.
It's important to note that Jefferies' findings regarding the iPhone 6C are based on its industry survey. This likely means Jefferies spent time observing and analyzing the activities of Apple's suppliers, leading it make certain conclusions about the products Apple may be developing.
Jefferies doesn't have any direct knowledge from Apple regarding its upcoming iPhones. And, even if the information Jefferies is getting is legitimate, there's always a chance things could change by the time Apple releases the product.
What's interesting, though, is that Apple reportedly plans to unveil this new product in the first quarter of next year, according to Jefferies. Apple typically introduces its new iPhones in September. And, although it follows the 'C' naming convention introduced with the iPhone 5C, Jefferies believes this iPhone 6C will have a metal casing instead of the colorful plastic found on the iPhone 5C.
This isn't the first time we've heard about Apple developing a new 4-inch iPhone. Earlier this month, Chinese news publication Economic Daily reported that display manufacturer AU Optronics is working on 4-inch screens for a new iPhone.