not all manufacturers make third round hips . these look like Marley major tiles . Marley for one don't do third round .
one comment , looks like hip trays are missing
the channels are different and a Marley Ludlow plus is dead flat and a 49 does have a camber from top to bottom .. but if it's a full line from bottom to top of the roof and not a mix . you might get away with it .
both are still available
the redjand I think you mean mini stonewold .. almost the same as moderns but not exactly .
if you are thinking of mixing them in then it won't work perfectly .
You would have noted the design then .
For 10 degrees they are to be clipped not nailed .
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