Mechanical: custom housing molds, exclusive colors, laser-engraved or silk-screened logos. Functional: 2D barcode engines, UHF RFID modules, NFC readers and biometric sensors as modular additions. Interfaces: RS232 or RS485 serial ports, custom aviation plugs, extra LAN. Core: processor tier, RAM and ROM capacity, and high-brightness panels for outdoor use. Related: customisation scope.