Apex (diacritic)
The shape and length of the apex can be different. It can even sometimes be different within the same writing. While pretty much all apices are made up of a line sloping up to the right, the line can be more or less curved, and is different in length from less than half the height of a letter to more than the height of a letter. Sometimes, it is put at the top with a hook, pointing out to the left. Rather than being centered over the vowel it changes, the apex is often drawn to the right.