The Zero Water 2 Pack Portable 5 Stage Filtration Travel Bottle Filters are designed for use with travel bottles and tumblers, featuring a 5-stage filtration system that includes carbon/charcoal filtration to remove micro-organisms. Made of durable plastic in a sleek white color, these portable filters are suitable for household use and come in a convenient 2-pack set. The ZeroWater brand is known for its high-quality water purification products, making these filters a reliable choice for on-the-go filtering needs. Each filter is designed to be easy to use and provide clean, safe drinking water wherever you are.