Those are spool pins.
Along with mushroom, and serrated pins they are broadly known as security pins.
They hinder picking if you apply too much tension, but if you simply learn to use the right amount of tension they generaly offer little hindrance.
Changed the order the pins are in, put a big bottom pin next to a little pin, if you want to make it quite hard then go: big, small, big, small, big... that'll make it more... fun.
Congrats on your locks you've picked.
