What does the flex number mean on a composite hockey stick?

Answer 1

It stands for the level of flexibility in the stick

there are three types of composite sticks: junior, intermediate, and senior

67 and below is recommended for ages 12 and below

87 and below is recommended for ages 13-16 years

anything higher than 90 for anyone above age 16

Answer 2

The flex in a hockey stick refers to how much whip the stick has. If you look up images of a hockey stick flexing, you can see it bend and the flex number indicates how much it will bend on a shot.