Helmet Modification, Is it ok?
PER Little League International, ANY modification to helmets MUST have that manufacturer’s approval.
According to https://www.littleleague.org/playing-rules/modifying-helmets-with-additional-attachments/
“The safety of all our participants is our utmost concern, and, like the vast majority of youth organizations, Little League® requires our batters to wear helmets that meet National Operating Committee on Standards for Athletic Equipment (NOCSAE) specifications and bear the NOCSAE stamp.
As the popularity of helmet attachments (c-flap, etc.) increase throughout baseball and softball, Little League® International has begun to receive inquiries from our families, players, and volunteers as to whether or not they’re permitted in Little League play.
Altering a helmet in anyway (drilling holes, removing padding, etc.) may cause a manufacturer to void the NOCSAE certification of that helmet, making it illegal to use in Little League play. If you have altered your helmet or intend to, please contact the helmet manufacturer to determine if altering the helmet will void the NOCSAE certification."
You can go to this website for Little League International and check to see if the manufacturer has already approved a face mask or cheek flap.