Expiration Date: February 2027 Series Name: Mirable (Science) Brand Name: Science Product Name: Tornado Stick [Set of 3] Manufacturer: Science / Science Product Details: This is the Tornado Stick used with Mirable Plus. The replacement period for the Tornado Stick is approximately 3 months. The replacement period for the Tornado Stick is "3 months for a family of 4 using it daily (based on a water flow of 100L)". Therefore, if the frequency of use is low, the chlorine removal effect will last longer. However, depending on the water quality and temperature, it may be necessary to replace it sooner, or the white granules (calcium sulfite) inside may dissolve and clump, weakening the water flow. In such cases, replacement is required even if the replacement period has not been reached. Please understand this before use.