[IREFU2]

SECTION 5 TEAM MEMBER'S EQUIPMENT, APPAREL
The referee shall not permit any team member to wear equipment or apparel which, in his/her judgment, is dangerous or confusing to other players or is not appropriate. Examples of illegal items include, but are not limited to:
ART. 1 . . . Illegal guards, casts or braces.

a. A guard, cast or brace made of hard and unyielding leather, plaster, pliable (soft) plastic, metal or any other hard substance may not be worn on the elbow, hand, finger, wrist or forearm; even though covered with soft padding.
b. Hard and unyielding items (guards, casts, braces, etc.) on the upper arm or shoulder must be padded.
c. Knee and ankle braces are permitted but all exposed hinges must be covered. Most over-sleeves recommended by manufacturers are acceptable. These braces may be padded or unpadded.

The key is line C.