Section 2: Equipment
The football is governed by Law 4. It must be of symmetrical oval shape, 720-730 millimetres in circumference and 545-555 millimetres transverse circumference, and inflated to a pressure of 69 kPa (Law 4.1). Supply and selection of match footballs is dealt with separately (Law 4.2).
Teams and players, including the numbered guernsey by which a player is identified, are dealt with under Law 5; changing a guernsey during a match is specifically provided for (Law 5.4), as is the team sheet by which players are nominated (Law 5.3).
Boots, jewellery and protective equipment are governed by Law 9, which is a distinct Law from the football itself. It prohibits items likely to cause injury (Law 9.2), provides for inspection (Law 9.3), and empowers an Umpire to order a player off until an offending item is removed (Law 9.4).
Goal posts and behind posts are fixed equipment of the ground rather than player equipment, and their specifications sit with the playing surface (Law 3.3).