Gen 3 - 5.25" - 2 ohm rear speakers for "Advanced Audio" Ultras. Betters bass response than Gen 2 models due to new lighter weight speaker cone. New 1" titanium tweeter is very smooth sounding when played at high volume. Vented magnet properly controls heat for added reliability. Sound is tailored to cut through exhaust and wind noise when the bike is at speed. Speaker passed testing with 100 watt RMS running them for 8 full hours before power rating was given. Can take peaks of 250 watts.