In addition to paintballs and markers, players also need a "hopper" to hold their paintballs (this also includes the use of an agitating hopper that feeds the marker faster for a steady rate of fire) and an air source (like a bottle of carbon dioxide) to propel the paintball from the marker. Nitrogen or High Pressure Air can also be used to propel the ball. These are also held in a bottle-like container. These air sources are primarily used by people who play often and have tournament-grade markers.
Players must don a paintball mask and goggles (preferrably goggles with "thermal lenses" to avoid fogging) to avoid serious injury to the face, ears, and eyes. Regulated fields require masks, goggles and marker plugs or barrel covers to play on the field. The plugs and covers are used to prevent accidental firing of a paintball while not engaged in a game. Paintballs travel about 280 feet per second and getting hit with a paintball usually stings and leaves a welt or bruise on the skin. In general, getting hit by a paintball from far away hurts less then getting hit at close range. Also, getting hit can hurt more if the ball does not break, and instead bounces.
Players usually fall into two categories: recreational and tournament players. Tournament players take the game seriously, investing perhaps $2,000 in paintball gear. A top of the line paintball marker can cost $1,500 - $2,000. A recreational marker can however be purchased for $100 to $300.