Half-fill kettle and boil - unplug and place in an empty sink.
Slowly add contents of sachet and leave for 10 minutes.If any scale remains after 10 minutes, reheat solution until it starts to fizz (but DO NOT boil).
Pour solution away, and rinse kettle thoroughly with cold water. Fill with clean water, boil, empty, and then rinse once more with cold water.
Plastic Kettle Descaler
Oust Plastic Kettle Descaler is specially formulated to safely and effectively restore plastic kettles to their best by removing stubborn limescale buildup in just 10 minutes.