Replacement crystals are available.
Tear Blower is a make-up artist’s tool, consisting of acrylic glass filled with menthol crystals. Tear Blower can be used repeatedly until the menthol crystals lose their effectiveness. Tear Blower is refillable. Fill the end with cotton wool to act as a filter (do not pack the end too tight with cotton wool). Then fill with menthol crystals and close the acrylic glass tube by attaching the mouthpiece. Position the output tube about 10 cm from the actor’s eye, and blow into the mouthpiece. The menthol vapors that stream into the actor’s eyes produce immediate tears.