Coleman SaluSpa 4 Person Portable Inflatable Outdoor Spa Hot Tub, Black

4 (four) is a number, numeral and digit. It is the natural number following 3 and preceding 5. It is a square number, the smallest semiprime and composite number, and is considered unlucky in many East Asian cultures.

Black is a color that results from the absence or complete absorption of visible light. It is an achromatic color, without chroma, like white and grey. It is often used symbolically or figuratively to represent darkness. Black and white have often been used to describe opposites such as good and evil, the Dark Ages versus the Age of Enlightenment, and night versus day. Since the Middle Ages, black has been the symbolic color of solemnity and authority, and for this reason it is still commonly worn by judges and magistrates.

Black was one of the first colors used by artists in Neolithic cave paintings. It was used in ancient Egypt and Greece as the color of the underworld. In the Roman Empire, it became the color of mourning, and over the centuries it was frequently associated with death, evil, witches, and magic. In the 14th century, it was worn by royalty, clergy, judges, and government officials in much of Europe. It became the color worn by English romantic poets, businessmen and statesmen in the 19th century, and a high fashion color in the 20th century. According to surveys in Europe and North America, it is the color most commonly associated with mourning, the end, secrets, magic, force, violence, fear, evil, and elegance.

Black is the most common ink color used for printing books, newspapers and documents, as it provides the highest contrast with white paper and thus is the easiest color to read. Similarly, black text on a white screen is the most common format used on computer screens. As of September 2019, the darkest material is made by MIT engineers from vertically aligned carbon nanotubes.

An inflatable is an object that can be inflated with a gas, usually with air, but hydrogen, helium, and nitrogen are also used. One of several advantages of an inflatable is that it can be stored in a small space when not inflated, since inflatables depend on the presence of a gas to maintain their size and shape. Function fulfillment per mass used compared with non-inflatable strategies is a key advantage. Stadium cushions, impact guards, vehicle wheel inner tubes, emergency air bags, and inflatable space habitats employ the inflatable principle. Inflation occurs through several strategies: pumps, ram-air, blowing, and suction.

Although the term inflatable can refer to any type of inflatable object, the term is often used in boating to specifically refer to inflatable boats.

Outdoor(s) may refer to:

• Wilderness
• Natural environment
• Outdoor cooking
• Outdoor education
• Outdoor equipment
• Outdoor fitness
• Outdoor literature
• Outdoor recreation
• Outdoor Channel, an American pay television channel focused on the outdoors
• Outdoor Products

A person (pl.: people or persons, depending on context) is a being who has certain capacities or attributes such as reason, morality, consciousness or self-consciousness, and being a part of a culturally established form of social relations such as kinship, ownership of property, or legal responsibility. The defining features of personhood and, consequently, what makes a person count as a person, differ widely among cultures and contexts.

In addition to the question of personhood, of what makes a being count as a person to begin with, there are further questions about personal identity and self: both about what makes any particular person that particular person instead of another, and about what makes a person at one time the same person as they were or will be at another time despite any intervening changes.

The plural form "people" is often used to refer to an entire nation or ethnic group (as in "a people"), and this was the original meaning of the word; it subsequently acquired its use as a plural form of person. The plural form "persons" is often used in philosophical and legal writing.

A spa is a location where mineral-rich spring water (sometimes seawater) is used to give medicinal baths. Spa health treatments are known as balneotherapy. The belief in the curative powers of mineral waters and hot springs goes back to prehistoric times. Spa towns, spa resorts, and day spas are popular worldwide, but are especially widespread in Europe and Japan.

Tub may refer to:

• A tub (container):
  • a round or oblong container with or without a lid:
    • a plant pot
  • a shallow, plastic or paper container, typically with a lid or closure
  • Tub (unit), a former quantity for sale or butter or cheese
• A bathtub, a plumbing fixture for bathing
• Hot tub, a large bath or small pool designed to comfortably hold multiple persons
• Quarry tub, a type of railway or tramway wagon
• Slack tub, in blacksmithing, a quench
• Tub boat, an unpowered cargo boat used on early canals
• Twin tub, a type of washing machine
• Tub file, in computing, an early, primitive random access memory technology.
• Tub Welch, a baseball player.

TUB may refer to:

• TUB (gene)
• Citroën TUB, a light van
• Technische Universität Berlin (Germany)
• Transports Urbains du Beauvaisis, local public transport operator in northern France
• Tubuai – Mataura Airport (IATA airport code)

TUBS or Tubs may refer to:

• Time unit box system, a system for notating events that happen over a time period.
• Tokai University Boarding School in Denmark
• Ryan Tubridy, Irish television and radio presenter.