Your Capresso ST600 Coffee Maker relies on both the quality of your beans and the quality of your water to brew the best coffee possible. When the ST600’s Auto-on button starts flashing, you know it’s time to replace the oval-shaped charcoal filter that removes 83% of impurities and chlorine from your tap water. This pack of 6 charcoal filters ensures you fresh, pure coffee is just a few minutes away.