Dual-Action Filters: Ultra-fine holes filter firstly can filter impurities hair and dust comprehensively insured water clean. The coconut shell activated carbon secondly filters purify the water again keep the water fresh and no smell. Always keeps water clean and fresh let pets drinking healthy and growing happy. Pet Healthy Mom Happy Fits For: YOUTHINK ceramic drinking fountain Kindly Note: Clean the fitler every 3-4 days and replace filter every 2-4 weeks to maintain water freshness keep your famliy friends a happy life. Clean filter with water before use. Foam filter can only clean by water. Detergent is not allowed. Material: Activated Carbon Colth and Plastic Size: 2.3 x 0.8 x 1.8 inch (L x W x H). Package included: 4 x Carbon Replacement Filters 1 x Foam Filter