A space efficient hydrotherapy experience when area isn't large enough for a Softub 300. The 220 has a 6 foot outer diameter without any seating obstructions. This gives a couple of people enough room to stretch out and be comfortable. You won't find another therapy spa of this class, that holds 220 gallons of water and weighs only 67 pounds when empty! This is only possible because of Softub's ingenious patented material called Polybond.