Telescopic design features a total deployed height 7.30 m, against 4.25 m when collapsed. The 7.30 m height, compared to usual 4 or 6 m HF rods, features higher efficiency, notably in the lower part of the HF range. The antenna is made from high grade carbon fibre prepeg for higher stiffness and resistance. A custom feeder ensures a sealed penetration in the watertight box of the tuning unit (out of supply) located under the whip

Expendable UHF buoy. SLOT 281 is a single use buoy allowing covert one way transmission between a submerged submarine and airplanes or surface ships. A user adjustable delay allows the submarine to leave the area before the beginning of transmission. SLOT 281 has been designed with cost in mind to provide a cheap and reliable communication means to submerged submarines:

• The whole system is fully independent of submarine communication system;
• Control unit permits: message recording, and control, initial delay and life time setting, frequency choice. SLOT 281 is self-buoyant and features high reliability (no inflating device).