L Post (Standard): L bends are usually used for initial piercings because they are easy to get in. They are also a nice choice for someone who has trouble getting the U shaped screw in, or who likes to change their jewelry often. They are easy and relatively secure.
In this regard, is my nose piercing 18G or 20G?
The thickest Gauge is 18 Gauge. This would be your choice if you have recently had your nose pierced or wear that gauge normally. 20 Gauge is thinner than 18G and is the standard most popular size. If you are unsure this would be your best choice.
Subsequently, what size is the smallest nose stud?
1mm-1.5mm