It really is as simple as it looks, you put plumbers tape on the threads, screw the valve tail into the radiator (replacing the existing tails), the radiator now has the turn screw isolator tails which connects to the normal radiator valve & TRV. The TRV & radiator valve isolate the water in the central heating system, the isolator valve tails isolate the water in the radiator. You can even drain the radiator to work on it, change bleed screws etc. then refill the radiator prior to connecting it to the system, virtually eliminating the need to bleed as there is little or no air in the system.Hmm, does it come with pictures
It sounds far too simple.