Event for armour piece?

Hello,

So I am currently modding a pair of boots that when placed in your armour slot you gain speed and jump boost. The issue I have is in the events selection as I cannot find an event for when it is in an armour slot. Right now I have an if statement saying if entity has item in inventory then do potion. Also does anyone know where I can find the feather falling affect?

Please help,

Gaansy