Transom Wheels

My new-to-me Gregor 1244 has aluminum channel mounting brackets on the transom for securing launch wheels. Here is a pic of the starboard bracket.



I haven't seen them on a boat, but they seem like a good way to get the boat off the trailer to service the trailer, without having to set the transom on the ground (and jamming the transducer). Or to launch in very shallow water or where there is no improved ramp. Anyone used them or have recommendations?

Have seen plenty of the channels on boat transoms, but never the actual pedestals/wheels. Are they about the length and size of a tongue jack? Do they lock in place with a bolt/pin?

Yep, they are. On my tin there are holes in the brackets for securing with pins. I have seen them with hard rubber and inflatable wheels, guess it depends on the surface you will be using them on. But some input from those who have actally used them would be helpful.