Fluval A3977 Digital LED Dual Lamp Timer Suitable for freshwater and Saltwater aquariums Program sunrise, mid-day & dusk settings Control up to 2 LED lamps simultaneously (2 x 12V, 2 x 24V, or 1 x 12V/ 1 x 24V) On/off progressive dimming options Compatible with all LEDs featuring a standard 2.1 mm x 5.5 mm dc plug Connection