Mother K Silicone Brush is made with non-toxic material and was approved by US FDA. It’s outstanding durability can be used as semi-permanently compared to other sponge brush in the market. Dense silicone brush has 3 layers to make more foam and has outstanding cleaning power. It was designed with 360-degree revolution handle that makes it comfortable to use. It comes with 2 sets of brush (nipple brush and silicone brush).