It has become apparent that some players are wearing studs that do not comply with RFU Requirements
Michael Patz (RFU Match Official Development Manager) has pointed out the following:
It is incumbent upon manufacturers to be aware of the IRB Regulations and to ensure that they comply with the guidance provided. Players/parents then in turn have a responsibility to make sure the equipment they are buying/using complies.
Finally, the duty on the Match Officials is around the safety of the items they inspect at game time, and that they have the final decision as to whether a player can wear that item (including studs) during a game.
To view a document from the RFU which details the relevant requirements of Law 4, and a diagram that shows minimum and maximum dimensions for player' studs please click the links below
Please ensure players & parents are aware of the RFU Requirements for studs.
LAW 4 link -- http://alturl.com/z5ryg
CORRECT STUD SIZES link -- http://alturl.com/kemam