Hertz HMX 8-TW - 8" Marine high performance coax speakers black, set of 2

The coaxial speakers developed by Hertz are optimized to perform in an open space (other brands require an enclosed enclosure), with solid bass and excellent output. 

The tweeter - for the mid and high tones - has an acoustic lens that does not project the sound in a narrow beam, but rather a wide beam, which provides the best sound on, for example, an open boat where you do not have to sit exactly in the middle of the speaker for the best sound