Meets RTCA/DO-160G Section 21 Catergory M (for battery operation only; commercial aircraft, airborne equipment) standard.
All LCSU 4 units with RTCA approval are certified for use in aircraft.

Why an RTCA version?
The RTCA designation allows the LCSU 4 units to be battery operated in a commercial aircraft.

The LCSU 4 should not interfere with the aircraft’s electronics or instrumentation while being operated.

The appearance of both LCSU 4 units is essentially the same. However, the internal lining of the units is distinctly different. The new RTCA cases have been coated internally with a gold-coloured coating.

This coating helps minimize “electronic noise” emissions per the RTCA/DO-160G - Section 21, Environmental Conditions and Test Procedures for Airborne Equipment – Emission of Radio Frequency standard.