https://www.campingworld.com/garmin-8-pin-female-to-wire-block-adapter-for-gsd-24-sounder-319630.html
Garmin 8-Pin Female To Wire Block Adapter, GSD 24 Sounder
This Garmin adapter allows you to connect the wires on legacy 6-pin transducers with newer sonars that require an 8-pin connection.
garmin 8gsd 24pinfemale