Available on Request Hach Hach DPD Free Chlorine Reagent Powder Pillows, 2105569, 10ML, 100 Pcs/Pack These Free Chlorine Powder Pillow reagents are USEPA accepted for reporting in drinking water and wastewater analysis using Hach Method 8021. For best results use with a Hach colorimeter or... Available on Request Quick view Qty in Cart: 0 Price: Out of Stock Subtotal: Available on Request