Some of the modifications that were made on the former 737-700ER are a completely redesigned interior, different countermeasures against missiles, like IR-flares, chaff and ECM, as well as lots of antennas and less cabin windows are only some of the differences in comparison to the civilian basis. The most significant difference is the Northrop Grumman Electronic Systems Multi-role Electronically Scanned Array (MESA) radar, that is located above the fuselage as a "top hat".