Brush Master 4 in. diameter feed 15 HP 420cc Commercial Duty Chipper Shredder with Trailer Hitch, Gloves, Safety Goggles included

Fifteen or 15 may refer to:

• 15 (number), the natural number following 14 and preceding 16
• one of the years 15 BC, AD 15, 1915, 2015

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.

A brush is a common tool with bristles, wire or other filaments. It generally consists of a handle or block to which filaments are affixed in either a parallel or perpendicular orientation, depending on the way the brush is to be gripped during use. The material of both the block and bristles or filaments is chosen to withstand hazards of its intended use, such as corrosive chemicals, heat or abrasion. It is used for cleaning, grooming hair, make up, painting, surface finishing and for many other purposes. It is one of the most basic and versatile tools in use today, and the average household may contain several dozen varieties.

Commercial may refer to:

• a dose of advertising conveyed through media (such as radio or television)
  • Radio advertisement
  • Television advertisement
• (adjective for) commerce, a system of voluntary exchange of products and services
  • (adjective for) trade, the trading of something of economic value such as goods, services, information or money
• Two functional constituencies in elections for the Legislative Council of Hong Kong:
  • Commercial (First)
  • Commercial (Second)
• Commercial (album), a 2009 album by Los Amigos Invisibles
• Commercial broadcasting
• Commercial style or early Chicago school, an American architectural style
• Commercial Drive, Vancouver, a road in Vancouver, British Columbia, Canada
• Commercial Township, New Jersey, in Cumberland County, New Jersey

In geometry, a diameter of a circle is any straight line segment that passes through the centre of the circle and whose endpoints lie on the circle. It can also be defined as the longest chord of the circle. Both definitions are also valid for the diameter of a sphere.

In more modern usage, the length ${\displaystyle d}$ of a diameter is also called the diameter. In this sense one speaks of the diameter rather than a diameter (which refers to the line segment itself), because all diameters of a circle or sphere have the same length, this being twice the radius ${\displaystyle r.}$

${\displaystyle d=2r\qquad {\text{or equivalently}}\qquad r={\frac {d}{2}}.}$

For a convex shape in the plane, the diameter is defined to be the largest distance that can be formed between two opposite parallel lines tangent to its boundary, and the width is often defined to be the smallest such distance. Both quantities can be calculated efficiently using rotating calipers. For a curve of constant width such as the Reuleaux triangle, the width and diameter are the same because all such pairs of parallel tangent lines have the same distance.

For an ellipse, the standard terminology is different. A diameter of an ellipse is any chord passing through the centre of the ellipse. For example, conjugate diameters have the property that a tangent line to the ellipse at the endpoint of one diameter is parallel to the conjugate diameter. The longest diameter is called the major axis.

The word "diameter" is derived from Ancient Greek: διάμετρος (diametros), "diameter of a circle", from διά (dia), "across, through" and μέτρον (metron), "measure". It is often abbreviated ${\displaystyle {\text{DIA}},{\text{dia}},d,}$ or ${\displaystyle \varnothing .}$

A duty (from "due" meaning "that which is owing"; Old French: deu, did, past participle of devoir; Latin: debere, debitum, whence "debt") is a commitment or expectation to perform some action in general or if certain circumstances arise. A duty may arise from a system of ethics or morality, especially in an honor culture. Many duties are created by law, sometimes including a codified punishment or liability for non-performance. Performing one's duty may require some sacrifice of self-interest.

A sense-of-duty is also a virtue or personality trait that characterizes someone who is diligent about fulfilling individual duties or who confidently knows their calling. A sense-of-duty can also come from a need to fulfill familial pressures and desires. This is typically seen in a militaristic/patriotic way.

Cicero, an early Roman philosopher who discusses duty in his work “On Duties", suggests that duties can come from four different sources:

1. as a result of being a human
2. as a result of one's particular place in life (one's family, one's country, one's job)
3. as a result of one's character
4. as a result of one's own moral expectations for oneself

The specific duties imposed by law or culture vary considerably, depending on jurisdiction, religion, and social normalities.

Goggles, or safety glasses, are forms of protective eyewear that usually enclose or protect the area surrounding the eye in order to prevent particulates, water or chemicals from striking the eyes. They are used in chemistry laboratories and in woodworking. They are often used in snow sports as well, and in swimming. Goggles are often worn when using power tools such as drills or chainsaws to prevent flying particles from damaging the eyes. Many types of goggles are available as prescription goggles for those with vision problems.

Safety is the state of being "safe", the condition of being protected from harm or other danger. Safety can also refer to the control of recognized hazards in order to achieve an acceptable level of risk.

With or WITH may refer to:

• With, a preposition in English
• Carl Johannes With (1877–1923), Danish doctor and arachnologist
• With (character), a character in D. N. Angel
• With (novel), a novel by Donald Harrington
• With (album), a 2014 album by TVXQ
• With (EP), a 2021 EP by Nam Woo-hyun