The Rolls MX44 Pro 4-Channel Stereo Mixer is designed to mix up to four stereo line-level signals, such as CD, DVD, and MP3 players, laptops, and smartphones to a single stereo output.Each of the four channels includes a pair of RCAs and a stereo 3.5mm TRS inputs, while the mixer's output offers a pair of RCA and a stereo 3.5mm TRS connectors. Each channel features a level knob providing up to 30 dB of gain. The 3.5mm TRS output can also function as a headphone jack, providing enough power for most headphones. The MX44 Pro can be powered by an optional 9V battery or from the included 15 VDC power adapter.Specifications:Four stereo inputs to one stereo outputStereo RCA and 3.5mm TRS stereo high-impedance inputsStereo RCA and 3.5mm TRS stereo high-impedance outputBattery or AC operationItem Includes:Rolls MX44 Pro 4-Channel Stereo RCA & 3.5mm MixerRolls PS27s 15 VDC 100-240 VAC Wall Power AdapterLimited 1-Year Warranty3.5mm Stereo Male to Two RCA Stereo Male Y Cable