Suitable for KOSS Porta Pro PP Headphone. for KOSS Porta Pro PP Headphone. for KOSS KSC35, KSC75, KSC55, KSC50, KSC-10, KTX PRO1, KTX8, PTX6, KSC-11 KSC17, KSC7, KSC-12, CX6, KTX16, SA and UR5. Can enhance the bass performance of your headphone.
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