MKEK has taken to IDEF 2017 this year by releasing a 5.56x45mm NATO version of their 7.62x51mm NATO MPT-76, a Turkish made AR10. The select-fire, piston operated MPT-55 comes in two variants, a standard barrel configuration of 14.5 inches and 7.3 pounds, and a shorter version at 11 inches and 6.6 pounds designated the MPT-55K. There are some minor additions that MKEK has added to their 5.56x45mm design that differentiates it from a mil spec M4 or H&K 416. The pistol grip resembles that of a Hogue grip and appears to have an internal storage compartment within it. The trigger guard has been pushed out, possibly to accommodate for cold weather gloves. The buffer end plate has an incorporated sling attachment socket on either side, in addition, it has a magazine release catch on the left side that combined with the plate socket and a sling swivel embedded in the stock make it much more ambidextrous than a standard AR15. Magazines appear to be either a translucent variety or production polymer versions from Turkish company Safir Arms. Safir is an interesting company because magazines have been seen in use on Iranian production rifles and even with various Peshmerga elements.
The operational requirements for both of these rifles are for Turkish Special Forces to replace their Turkish license produced H&K 416s with 20,000 of these MPT-55s and MPT-55Ks. An example of one of these earlier 416 based versions-