Section 2: Equipment
The Football
The official NFL football (the "Duke") is made of cowhide leather with a pebble-grain texture. It must conform to the following specifications:
- Long axis: 11 to 11.25 inches (28–28.6 cm)
- Short circumference: 21 to 21.25 inches (53.3–54 cm)
- Long circumference: 28 to 28.5 inches (71.1–72.4 cm)
- Weight: 14 to 15 ounces (397–425 g)
- Inflation: 12.5 to 13.5 psi
Player Equipment (Mandatory)
- Helmet: NOCSAE-certified helmet properly fitted with four-point chin strap fastened. All helmets must pass laboratory performance testing. Players may select from a list of approved helmet models ranked by the NFL/NFLPA.
- Guardian Cap: Mandatory for all contact practices (preseason through postseason). Optional but not required during regular season games. Soft-shell protective covers worn over helmets to reduce impact forces. The NFL reports a 52% reduction in concussions during practice since adoption.
- Shoulder Pads: Properly fitted protective shoulder pads worn under the jersey.
- Thigh and Knee Pads: Required for all players and must be worn under the uniform pants.
- Mouthguard: Required for all players during play.
- Athletic Supporter/Cup: Required protective equipment.
Uniform Requirements
All players on a team must wear matching jerseys with individual numbers (1–99). Numbers must be clearly visible on the front and back of the jersey. Players at certain positions are restricted to specific number ranges, though the NFL expanded eligible numbers in 2021 to allow more flexibility.
Prohibited Equipment
- Hard, abrasive, or unyielding equipment or substances on hands, wrists, forearms, or elbows (unless medically required and approved)
- Stickum or any adhesive substance on body, uniform, or equipment
- Face mask openings smaller than specified minimums
- Jewelry of any kind during games or practice