3.5mm mono plug to 6.3mm mono jack FEV-B111By gerry / February 21, 2021 3.5mm mono plug to 6.3mm mono jack FEV-B111A. 3.5mm mono plug to 6.3mm mono jack;B. 3.5mm mono plug to 6.3mm stereo jackA. 3.5mm mono plug to 6.3mm mono jack; B. 3.5mm mono plug to 6.3mm stereo jack