Mehrton Summer Series 190. The Mehrton Summer Series 190 offers a wide range of international signal tones for the broadest application spectrum. It has been developed in the same housing as the Series 890, allowing it to be effortlessly combined with up to three signal lights to provide an acoustic and visual solution. It features 32 tones for versatile applications, an adjustable sound output of up to 110 dB, and 3 tones that can be triggered externally. It has an IP65 protection rating and includes mounts for easy combination with permanent signal lights/traffic lights from the Series 890.