Roller blind mechanism for 30mm (outer diameter) metal slotted tube with an internal diameter of 28mm, chain operated. You get the control end & idle end & metal fixing brackets which you can top or face fit.
NB size refers to the external diameter of the metal roller tube
All continuous chains must be secured using a chain tensioning device which must be fixed to a wall at least 1.5m above the floor.
To calculate maximum allowable chain length to comply with new safety regulations:
Max drop of chain = (Height of rail from floor in cm - 150cm)
So if your roller blind is fixed at 1800mm
Take away 1500mm. Your chain should be 300mm long.
All chains come with a safety device.
