\d{8}a digit, repeated exactly 8 times
-the literal - (4510 / 558 / 2D16)
{3}repeats the group contents below exactly 3 times:
\d{4}a digit, repeated exactly 4 times
-the literal - (4510 / 558 / 2D16)
\d{12}a digit, repeated exactly 12 times
g modifier: global. Finds all matches instead of stopping after the first
m modifier: multiline. Causes ^ and $ to match the start and end of each line, not only the start and end of the string