Standard Horizon MLS-310 Amplified speaker fully waterproof gives big sound to any VHF complete with flush and gimble mounting hardware.  Needs 12v supply 10 watt output with volume control.  Only available in black sorry.

Eagle waterproof horn speaker 135mm x 165mm deep 8 watts with mounting bracket. 8ohms with 3m cable and 3.5mm jack plug.

Eagle large white waterproof horn speaker  120mm x 200mm x 235mm. 8 ohm 30Watt

Small communications speaker on bracket or can be flush mounted 75mm x 66mm x 75mm deep

Eagle / Midland PA amplifier 20W with intercom system 12v/24v 2 inputs for mic and aux with level controls. Fog horn and siren built in (microphone and speakers not included) Unit also has a listening feature from the speakers back to the operator.  Great for large vessels and work boats etc.. 1 year warranty not waterproof for in-side use only.
60 x 170 x 185 mm

Eagle large white waterproof horn speaker  120mm x 200mm x 235mm. 8 ohm 30Watt

Raymarine 430 Loudhailer System with intercom and horn speaker