Harness Module M | Speaker Extension

Harness Module M | Speaker Extension. Easy to install, easy to remove, easy to repair!

Availability: In stock

Affordable modules eliminate the need for repairs or replacement harnesses. Simply plug in a new section if needed. Use this "M" speaker lead to add additional speakers to your system. Base harnesses A and A+ are built to accommodate one speaker. Add one M for each speaker being used after the first.


Wiring for an 8+ (3 Speakers)

1 x A+ Harness

2 x M Harness

1 x R Harness


Wiring for a 4+ (2 Speakers)

1 x A+ Harness

1 x M Harness

1 x R Harness


NOTE: Our Cox Box and Cox Box Mini Amplifier Systems are rated for a maximum of 3 speakers. Adding more than three speakers will overload the amplifier which will lead to some or all of the following: distorted sound, reduced volume, temporary amplifier shutdown, permanent amplifier damage.



  • Audio wire
  • 2 Cable Mounts
  • 2 Cable ties
  • 2 Alcohol swabs

CoxBox Boat Wiring

Extension cord for Harness Module A+. Connects to a speaker and to another speaker or modular harness.

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