What is meant by "90 degree ball"? That is, what is the difference between this (with 90 degree ball) and this (without)? If it means what I thought it meant, one of the pictures is wrong?
What is meant by "90 degree ball"? That is, what is the difference between this (with 90 degree ball) and this (without)? If it means what I thought it meant, one of the pictures is wrong?