Sometimes you don’t have the space or the inclination for a full-size pool. That is when a spa (hot tub) or spool may be just the thing. In this case, your spa-only will likely be larger than the average spa-pool combo or have extra features. A spool is a spa with a shallow area (typically called a tanning or Baja shelf) adjacent to it. Either way, when space is limited or you are only looking for a dip, these are perfect options.