You need a y cable to use your transducer with,the Mega 360 in combination. For Helix models, 9 M360 2DDI Y is the cable. Because the Mega 360 is not plugged into the network and in the back of your helix or Solix, the Helix unit’s must be a g3n Plus unit starting with the size of helix 8 SI+ G3N as it plugs into where the transducer port is or a Y cable. If using the Y cable with a Helix 9 SI G3N, no y cable offered by Humminbird is wired to show SI. It will only show 2d and DI because you will get your SI by using the Mega 360 and it’s a good as your transducer pic when using the Mega 360 in SI setting. I use the Mega 360 when trolling crankbaits at a speed of 1.4 to 2.2 mph with no issues set at a sweep speed of 3 and even sometimes 4. Give me a really good pic of fish, structure, baitballs, you name it. I have no issues but slower speeds will be more clear than fast. The Mega 360 can only be plugged into a G3N Plus unit, but once plugged into the Plus unit,,can be networked to other Helix units that have the software version 2.18 to run the mega 360. Solix units require a different software other than what Helix is offered also.