LAW 4: Players' Equipment/Jerseys/Shin Guards/Casts/Splints/Orthopedic Braces/Jewelry

Player equipment must include a jersey (with a unique number at least six inches high.) In a case where the visiting team and the home team have similar colored jerseys, the home team must change to a markedly different jersey color. Pinnies worn over a numbered uniform shirt are acceptable; otherwise, substitute uniform shirts must conform to the requirements for numbering. 

Players with plaster casts or hard splints, even if padded, cannot play—even with the permission of a parent or medical approval. Players with orthopedic braces that have exposed, or uncapped metal parts are also not allowed to play. Jewelry shall not be worn except for medical alert bracelets. A medical alert bracelet must be taped and may be visible. IFAB mandates no jewelry—see the IFAB Laws for the rest of the requirements.