The pillow style tank, also commonly referred to as a bladder tank comes in three different styles depending on your water transfer needs. A gray tank indicates it is for gray water meaning it is not intended for consumption but should be used for example in crop spraying, watering nurseries, feeding livestock, to name a few. If drinking water is needed then choose the sky blue tank for potable water transfer. Its construction is FDA approved coated rugged PVC vinyl and carries a 7 year warranty. Certification of all tanks meets 8128 FDA specifications. Models priced below are designed for chemical resistance, ideally suited for transport of fertilizer, pesticides, or herbicides. It is intended for agricultural usage and should not be used for petroleum storage. Models up to 2500 gallon capacity are carried UPS when shipped, larger models will come via common carrier on a pallet.