I do not think brand fixtures are any different to be honest. However should one or the other NOT have the 'slot/runners' on the roll out you would have to buy some aluminium section and fix it with screws/nut/bolts to underside of the roll out rail. I don't honestly think that would be necessary on more recent models.
To get the Kampa awning to connect to either will be no problem. But you would need to know the length of the 'Tunnel' beading on the awning. If it is longer than the roll out awning rail with the slots in...then it will more than likely be larger that it should be. If the beading on the tunnel is shorter than the slot on the roll out, you will require a stop end, this prevents in windy conditions the tunnel of awning traveling along the rail. Next thing to be aware of, and I have no idea if you have a van with say...a garage, that your awning does not foul it. ie you want to have access to it. So it would need to be outside of said door or inside of door. The same goes for habitation/cab door etc. Then your need to get some kador rail ( a webbing with beading each side) and a couple of sections of figure of eight IF you intend to use a drive away awning. Hope this helps.
Hi AUSTINS thanks for that. We have an Autotrail Apache 700SE which has a 4m Thule Omnistore 5002 Awning. I have got hold of a second hand Kampa Motor Rally 390L which has the correct hight for the awning to attach to.
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