Airing Cupboard Moth Killer and Freshener 2 "You need hands of steel to make this work!" Mrs Aileen Taylor 11 September 2017 I could not operate this device and although it is in the wardrobe I wanted it for, I am not at all sure it is working. A note from the team To activate it may be easier to clasp both hands around the unit and use both thumbs pressed firmly on the plunger. Some force is needed to press plunger down but the plunger only needs to break the seal for the solution to activate. You'll see the purple rise once it's activated, the plunger does not need to be fully depressed. We've emailed to help.