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Equipment

The only essential equipment in a basketball game is the ball and the court: a flat, rectangular surface with baskets at opposite ends. Competitive levels require the use of more equipment such as clocks, score sheets, scoreboards, alternating possession arrows, and whistle-operated stop-clock systems.

A regulation basketball court in international games is 28 meters (92 feet) long and 15 meters (49 feet) wide. In the NBA and NCAA the court is 94 by 50 feet (29 by 15 meters). Most courts have wood flooring, usually constructed from maple planks running in the same direction as the longer court dimension. The name and logo of the home team is usually painted on or around the center circle.

The basket is a steel rim 18 inches (46 cm) diameter with an attached net affixed to a backboard that measures 6 by 3.5 feet (1.8 by 1.1 meters) and one basket is at each end of the court. The white outlined box on the backboard is 18 inches (46 cm) high and 2 feet (61 cm) wide. At almost all levels of competition, the top of the rim is exactly 10 feet (3.05 meters) above the court and 4 feet (1.22 meters) inside the baseline. While variation is possible in the dimensions of the court and backboard, it is considered important for the basket to be of the correct height – a rim that is off by just a few inches can have an adverse effect on shooting. The net must "check the ball momentarily as it passes through the basket" to aid the visual confirmation that the ball went through. The act of checking the ball has the further advantage of slowing down the ball so the rebound does not go as far.

The size of the basketball is also regulated. For men, the official ball is 29.5 inches (75 cm) in circumference (size 7, or a "295 ball") and weighs 22 oz (620 g). If women are playing, the official basketball size is 28.5 inches (72 cm) in circumference (size 6, or a "285 ball") with a weight of 20 oz (570 g). In 3x3, a formalized version of the halfcourt 3-on-3 game, a dedicated ball with the circumference of a size 6 ball but the weight of a size 7 ball is used in all competitions (men's, women's, and mixed teams).