Features: Do you have 4 power amplifiers and 4 sets of speakers that need to be connected together? A powerful amplifier and speaker selection switcher can solve the above problems. 1. Four power amplifiers use push-button self-locking switches to select and switch inputs, and four groups of stereo speakers use push-button self-locking switches to select and switch outputs 2. It can use a banana head interface or accept up to 12 AWG speaker cables. Fully compatible with all types of amplifiers and speakers. 3. The 6.35mm headphone jack provides stereo headphone output for personal listening signal monitoring, and the headphone output has volume adjustment. Stereo speakers supporting impedance from 4 to 16 ohms, with each channel supporting a maximum power of up to 300W Input and output can be manually and switched, with plug-and-play functionality. The switching signal is stable, and there be no interference or noise between channels Compact design, sturdy metal casing, easy installation, and no external power supply required for the product Simple installation: The input and output are plug-and-play, making installation convenient and allowing you to enjoy a audio experience Product Parameters: Material: Metal Color: Black Compatible with all types of power amplifiers and speakers. The input/output accepts heavy-duty speaker wires or speaker pin wires through the terminal port. Connect the power amplifier to the A-B-C-D positions of the amplifier. Connect the speakers to positions 1, 2, 3 and 4 of the speakers respectively. Turn on your power amplifier stereo device. The product does not require an external power supply. Input/Output: 4 groups of input /4 groups of output (4mm banana plug) Package Contents: 1 x Amplifier Speaker Selector Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.