David Cohen in New Scientist:
All you do is fire a rope to the top of the structure using a harpoon gun or grappling hook, and then fit the rope into the device, called PowerQuick, which attaches to your climbing harness. Then just sit back and squeeze a lever.
PowerQuick has been developed by Quoin International based in Carson City, Nevada, and can lift a load of 145 kilograms at a rate of 1 metre per second. A battery-powered motor turns a series of wheels and cogs to pull the rope through the device. One battery charge is enough to scale the Statue of Liberty five times, or 250 metres in total. If you let go of the device it automatically stops and holds its position, and it can also be used for a slow controlled descent.