Sena 60S Speakers With Sound By Harman Kardon Replacement Harmon Kardon 40mm speakers for the Sena 60S Bluetooth Headset. Features: Direct replacement speakers for the Sena 60S Bluetooth Headset. 40mm speakers with Harmon Kardon sound Higher sound output and increased audio resolution with wider dynamic range compared to 1st generation Includes: 60S Harman-kardon Speakers, hook and loop fasteners for speakers and thick speaker pads