It is interesting to see the adaptability of this 'bent pipe' tripod type mount with the two support struts.  I've seen this same geometry arrangement used for dish sizes up to 1.8m.  Sometimes the two short struts have adjustable lengths.  Anyway, the above mount design is very versatile, suitable for horizontal surfaces, vertical walls and sloping rooofs as well as, in this case, large rocks !

Best regards, Eric.