Warm Tips The SP220S version has a volume control button that can adjust the volume of the audio sourceFeatures 2IN4OUT Audio selector, the input can be connected to 2 amplifiers, and the output has 4 interfaces, which can be connected to speakers.The panel has push buttons for input and output switching, manual switching, stable sound without interference no need to plug in, easy to use and energy saving.There is a nonslip pad on the bottom to protect your deskUsing audio equipment with a switch can avoid interface wear caused by plugging in and out, and etend the life of the audio equipment.Parameters SP24B Version Audio Input Stereo RCA2 Audio Output Stereo RCA4 Dimensions WDH 16012040mm6.304.721.57in Net Weight 270g0.60lbPackage Weight 500g1.10lb SP24 Version Audio Input Speaker Jacks2Audio output Speaker jacks 4 Dimensions WDH 16012040mm6.304.721.57in Net weight 270g0.60lbPackage Weight 500g1.10lb SP220S Version Audio Input Stereo RCA2 Audio Output Stereo RCA4 Dimensions WDH 14316062mmPacking list1Speaker selector