What it does Combines (mixes) two stereo audio inputs into one mixed stereo output. Provides two identical stereo 3.5mm outputs so the same mixed signal can feed two headphones or two amplifiers at once. Key benefits — why you need it Simple audio mixing: merge two different sound sources (for example, a phone and a laptop) without extra equipment. Easy sharing: connect two headphones or two amplifier/speaker inputs simultaneously to listen to the same mixed audio. Standard compatibility: all sockets are stereo 3.5mm, compatible with most phones, tablets, laptops, MP3 players, PCs, headphones and consumer audio gear. How it works (important details) All jacks are stereo 3.5mm. Inputs are one-way (designed to send signals into the unit). The unit mixes those inputs. Both outputs deliver the same mixed stereo signal (no left/right swapping or independent outputs). You can plug both inputs in at the same time and they will be mixed together; you can also plug both outputs in at the same time to feed two devices. Practical attributes Function: passive mixing and dual stereo output. Compatibility: standard 3.5mm stereo connectors for broad device support. Performance: produces a single mixed stereo output from two simultaneous stereo inputs; both outputs mirror that mixed signal. Example use scenarios Travel/entertainment: Two people share the same mixed audio from two sources via two headphones during a flight or commute. Small presentations or parties: Feed a mixed signal from a phone and laptop into two amplifiers or speakers so both playback devices receive the same audio. Simple studio/demo setup: Combine a playback device and an auxiliary source into one mixed feed and monitor the result on two headphone outputs. No extra switching or special adapters required — plug your stereo 3.5mm cables into the inputs and outputs and the unit provides a single mixed stereo signal to both outputs.