I made my own from 1-Minelab [h=1]Headphone Adaptor Cable 3.5mm (1/8") to 6.35mm (1/4") from Minelab.
- cut off the 1/4" connector end attach one half of a waterproof connector then: [/h]
2) ¼" Headphone Adapter PN: 1626000.....$39.95 from Garrett.
- cut off the 1/4" connector end and attach the other half of the waterproof connector.
Minelab has wiring instructions on their website.
With the adapter I made I can easily use any Garrett AT(series) compatible headphone with the Minelab 600/800 detectors and retain the interchangeability of the headphones between the Minelab and Garrett detectors.
Here are the pics. The Garrett adapter has a very short lead cable, you only get one change in putting it together with one part of the waterproof connector. Part numbers are with the Minelab and Garrett parts, I do not have any info on the waterproof connectors from an auction site. The ones I got had four connectors, you could use two or three connector also as you only need two for the Equinox. Hope this helps.
If you talk with the repair tech at Kellyco he is very familiar with this he haas all the info you need I forgot his name but he gets the phone 99 percent of the time.