RESIN FILTER (for Gravity Fed Iron) Sale! from $ 24.60 Qty. Add to Cart This item is currently on backorder but you can still purchase it now and we'll ship as soon as more become available. STOP CHANGING MESSY WATER BOTTLE RESIN WITH THIS INLINE FILTER. Resin Filter for use with a gravity-fed water bottle. Eliminates the mess associated with replacing resin in water bottles. Cleanses impurities and hard-water deposits. Blue beads turn brown (amber/rust) when it is time to change the filter. Contains 3 oz. of resin Longevity of resin depends on how often the iron is used and type of water being used. It also removes calcium and magnesium and can reduce lime and scale buildup. Size: 5" long. Tweet