Peak power is a type of measurement used in the electrical and nautical sectors to define the power of stereo or fishfinders.

For a loudspeaker or stereo system, the power expressed in peak watts is commonly equivalent to the RMS power multiplied by 8. In practice, a peak power of 80 watts is equivalent to an RMS power of 10 watts.
When the type of power measurement is not indicated, the peak power is normally meant.

Even in an fishfinder, the peak power is equivalent to 8 times the RMS power value.