Optional cable/connector assemblies custom-made to your requirements. Adding EQplus to a W2IHY 8-Band EQ requires a DIN-to-DIN cable from 8-Band output to EQplus aux in. If you are already using mic cables made for W2IHY EQs, you'll be glad to know EQplus follows identical conventions for output-to-radio wiring. So, the cables are fully interchangeable.