This logo indicates that a car loudspeaker has been tested to CTA-2031, Testing and Measurement Methods for Mobile Loudspeaker Systems. The standard requires that the manufacturers report: primary power output in watts, cut-out diameter, mounting depth, impedance and maxium rms power output in watts, total harmonic distortion (THD) plus noise and signal to noise ratio.
It's partner mark, the CTA-2006-B Mobile Amplifier Power logo, indicates that a car amplifier has been tested in accordance with CTA-2006-B Mobile Amplifer Power. CTA-2006-B defines test procedures for rating the performance of mobile amplifiers and requirements for reporting the performance.
When consumers use the information found with both logos, they will be able to select mobile loudspeakers with power handling capabilities that are appropriate for the power output characteristics of their mobile amplifiers.