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1.12 The catcher may wear a leather mitt not more than thirty eight inches in circumference, nor more than fifteen and one half inches from top to bottom. Such limits shall include all lacing and any leather band or facing attached to the outer edge of the mitt. The space between the thumb section and the finger section of the mitt shall not exceed six inches at the top of the mitt and four inches at the base of the thumb crotch. The web shall measure not more than seven inches across the top or more than six inches from its top to the base of the thumb crotch. The web may be either a lacing or lacing through leather tunnels, or a center piece of leather which may be an extension of the palm, connected to the mitt with lacing and constructed so that it will not exceed any of the above mentioned measurements.

1.16 A Professional League shall adopt the following rule pertaining to the use of helmets:
(d) All catchers shall wear a catcher's protective helmet, while fielding their position.

2.00 Definitions of Terms.
(All definitions in Rule 2.00 are listed alphabetically.)

ADJUDGED is a judgment decision by the umpire.

An APPEAL is the act of a fielder in claiming violation of the rules by the offensive team.

The BATTERY is the pitcher and catcher.

A BUNT is a batted ball not swung at, but intentionally met with the bat and tapped slowly within the infield.

The CATCHER is the fielder who takes his position back of the home base.

The CATCHER'S BOX is that area within which the catcher shall stand until the pitcher delivers the ball.

FAIR TERRITORY is that part of the playing field within, and including the first base and third base lines, from home base to the bottom of the playing field fence and perpendicularly upwards. All foul lines are in fair territory.

A FOUL BALL is a batted ball that settles on foul territory between home and first base, or between home and third base, or that bounds past first or third base on or over foul territory, or that first falls on foul territory beyond first or third base, or that, while on or over foul territory, touches the person of an umpire or player, or any object foreign to the natural ground. A foul fly shall be judged according to the relative position of the ball and the foul line, including the foul pole, and not as to whether the infielder is on foul or fair territory at the time he touches the ball. A batted ball not touched by a fielder, which hits the pitcher's rubber and rebounds into foul territory, between home and first, or between home and third base is a foul ball.

FOUL TERRITORY is that part of the playing field outside the first and third base lines extended to the fence and perpendicularly upwards.

A FOUL TIP is a batted ball that goes sharp and direct from the bat to the catcher's hands and is legally caught. It is not a foul tip unless caught and any foul tip that is caught is a strike, and the ball is in play. It is not a catch if it is a rebound, unless the ball has first touched the catcher's glove or hand.

IN FLIGHT describes a batted, thrown, or pitched ball which has not yet touched the ground or some object other than a fielder.

IN JEOPARDY is a term indicating that the ball is in play and an offensive player may be put out.

An INNING is that portion of a game within which the teams alternate on offense and defense and in which there are three putouts for each team. Each team's time at bat is a half inning.

INTERFERENCE

(a) Offensive interference is an act by the team at bat which interferes with, obstructs, impedes, hinders or confuses any fielder attempting to make a play. If the umpire declares the batter, batter runner, or a runner out for interference, all other runners shall return to the last base that was in the judgment of the umpire, legally touched at the time of the interference, unless otherwise provided by these rules. In the event the batter runner has not reached first base, all runners shall return to the base last occupied at the time of the pitch.

(b) Defensive interference is an act by a fielder which hinders or prevents a batter from hitting a pitch.

(c) Umpire's interference occurs (1) When an umpire hinders, impedes or prevents a catcher's throw attempting to prevent a stolen base, or (2) When a fair ball touches an umpire on fair territory before passing a fielder.

On any interference the ball is dead.

A LIVE BALL is a ball which is in play.

OBSTRUCTION is the act of a fielder who, while not in possession of the ball and not in the act of fielding the ball, impedes the progress of any runner. If a fielder is about to receive a thrown ball and if the ball is in flight directly toward and near enough to the fielder so he must occupy his position to receive the ball he may be considered "in the act of fielding a ball." It is entirely up to the judgment of the umpire as to whether a fielder is in the act of fielding a ball. After a fielder has made an attempt to field a ball and missed, he can no longer be in the "act of fielding" the ball. For example: an infielder dives at a ground ball and the ball passes him and he continues to lie on the ground and delays the progress of the runner, he very likely has obstructed the runner.

An OUT is one of the three required retirements of an offensive team during its time at bat.

OVERSLIDE (or OVERSLIDING) is the act of an offensive player when his slide to a base, other than when advancing from home to first base, is with such momentum that he loses contact with the base.

The PERSON of a player or an umpire is any part of his body, his clothing or his equipment.

A PITCH is a ball delivered to the batter by the pitcher. All other deliveries of the ball by one player to another are thrown balls.

"PLAY" is the umpire's order to start the game or to resume action following any dead ball.

A QUICK RETURN pitch is one made with obvious intent to catch a batter off balance. It is an illegal pitch.

A RETOUCH is the act of a runner in returning to a base as legally required.

A RUN (or SCORE) is the score made by an offensive player who advances from batter to runner and touches first, second, third and home bases in that order.

"SAFE" is a declaration by the umpire that a runner is entitled to the base for which he was trying.

SQUEEZE PLAY is a term to designate a play when a team, with a runner on third base, attempts to score that runner by means of a bunt.

A STRIKE is a legal pitch when so called by the umpire, which_
(a) Is struck at by the batter and is missed;
(b) Is not struck at, if any part of the ball passes through any part of the strike zone;
(c) Is fouled by the batter when he has less than two strikes;
(d) Is bunted foul;
(e) Touches the batter as he strikes at it;
(f) Touches the batter in flight in the strike zone; or
(g) Becomes a foul tip.

The STRIKE ZONE is that area over home plate the upper limit of which is a horizontal line at the midpoint between the top of the shoulders and the top of the uniform pants, and the lower level is a line at the hallow beneath the knee cap. The Strike Zone shall be determined from the batter's stance as the batter is prepared to swing at a pitched ball.
A TAG is the action of a fielder in touching a base with his body while holding the ball securely and firmly in his hand or glove; or touching a runner with the ball, or with his hand or glove holding the ball, while holding the ball securely and firmly in his hand or glove.

A THROW is the act of propelling the ball with the hand and arm to a given objective and is to be distinguished, always, from the pitch.

"TIME" is the announcement by an umpire of a legal interruption of play, during which the ball is dead.

TOUCH. To touch a player or umpire is to touch any part of his body, his clothing or his equipment.

A WILD PITCH is one so high, so low, or so wide of the plate that it cannot be handled with ordinary effort by the catcher.