The client required a redundant high speed link to their DR site that is 800m away from their main building. Due to obstacles, we erected a 9m climbable mast to the building roof and installed a 24Ghz Airfiber link and a NanoBeam 5.8Ghz backup link.
The best thing about this mast is that it is attached to a hinged baseplate, making it very easy to lower and raise if required. A boat winch works well for this purpose.
The two devices are bonded using Mikrotik CCR routers at each end for seamless failover.