NOTE: Formalin or formaldehyde is classified as a hazardous chemical (This Formacide-B will be available in Quart size at a later date) Formaldehyde is used as an external paraciticide and fungicide. This is the FDA approved version of Formalin (Formaldehyde, 37%) for treatment on fish. Shipping Information: UPS requires a $25.00 Haz-Mat fee be applied to the shipping cost of this item. This fee is built into the cost of this item. At the present time there is no special packaging charge.