When I purchased my unit 3 years ago directly from them, they gave me everything needed to install except for the circuit breaker and supply wire. They also customized my package and shipped extra supply vents so I could vent the aft cabin.
Package contained
Ac unit its self
Control pac
T stat and wire
Water pump, thru hull seacock and all fittings, hose, clamps
4"Teak vents cover plates
Teak supply cover
4" & 6" flex duct
Supply feed with dampeners
Like I said everything you need to install.
I was going the buy the unit online from a marine supply store, I called mermaid technical support to confirm the correct size and to ask a few questions. Dave is very helpful and price matched distributor so I bought the unit directly from them. Like I said before they customized my kit so I didn't have to buy anything I did not need for my instalation.
Very happy with my unit. I had a minor warranty issue with my unit, bad valve which I my have damaged during the installation. They repaired unit within 24 hrs and shipped it back to me within a few days.