OK so I just got done compiling a current mostly complete list of Thule roof rack gear carriers and compatibility with the Thule PRO series commercial truck racks.
The complete list can be found here...
Thule Xadapt / Thule Pro Series truck racks compatibility list
There is a lot of confusion out there because the Thule Pro Series truck rack bars are not the same as the Thule Xsporter truck rack bars. Thule Racks has worked hard to enable most Thule gear carriers to connect directly to the elliptical Xsporter bars. Previously many of the Thule Xadapts were needed. These are adapters that insert in the T-Slot found on the top of the bars that then allow you to connect the gear carrier to the Xadapt.
The Thule PRO series truck racks have larger dimension bars, enabling them to carry the commercial loads they are designed for. But they also have the T-Slot in the top of each bar too, so now the Thule Xadapts are back in business because they enable compatibility of most Thule gear carriers with the Thule PRO series truck rack bars when you want to get sporty with your commercial rack and maybe want to attach Thule kayak carriers and other Thule sport carriers on the Thule PRO series bars.
So here's the current Thule watersport carrier lowdown:
THULE WATERSPORT CARRIERS & ACCESSORIES
Thule 897XT Hullavator attaches directly to Thule PRO Series bars
Thule 835PRO Hull-a-Port needs Xadapt3
Thule 835XTR Hull-a-Port needs Xadapt3
Thule 835XT Hull-a-Port needs Xadapt3
Thule 825 PortSide needs Xadapt3
Thule 887 Slipstream needs Xadapt3
Thule 830 Stacker needs Xadapt3
Thule 877XT Hydro-Glide needs Xadapt3
Thule 878XT Set to Go needs Xadapt3
Thule 875XT Hydro-Glide needs Xadapt3
Thule 883 Glide and Set needs Xadapt3
Thule 839 Get-a-Grip kayak paddle holder needs Xadapt3
Thule 554XT surfboard rack needs Xadapt3
Thule 597XT canoe rack not compatible but the included Thule Load Stops that are packaged with the Thule Pro series truck racks work very well for carrying a canoe.