The Icom SP-30 is not your typical mobile speaker.
The quality 4" speaker element has a heavy magnet and handle up to 20 watts input (40 watts peak). 4 Ohms.
It has an adjustable bracket allowing over or under mounting.
A 6 foot audio cable wired from the rear panel terminates to two wires
which may be inserted into the supplied cable adapter with 3.5mm mono mini plug.