when you buy pinz and syringes, it is best to buy a syringe/pin combo with the pin being the size you want to draw the fluid out of the vials, and get seperate loose pinz in the size you want to inject with. anotherwards your order should look like this:
pin/syringe combo in 3cc-20g-1.5"
pin only in 22,23, or 25g
get a sealed unit of 100 of each and you will be fine. this will allow you to just open up a syringe with attached needle, draw up the required amount of product, then remove the now dull pin and stick a new loose pin on the syringe in the size you wanted to inject with.