Easi Bleed was invented to solve the old problem of "broken radiator bleed valves". It is very common for the "radiator air vents to round off", get painted over, snap off or just sieze up.
Before now the only way to sort the problem out was to call out a plumber and have them drain down you "central heating system" and "replace the broken radiator bleed valve". Some times it is not possible to remove the "bleed valve" as it has locked up or round off due to the age of the radiator. So then the only option would be to change the radiator or the air vent itself. The bill for just changing the "radiator air vent" itself would between £110 to £190. to change your radiator it would cost in excess of £250.