so I recently got my first mech mod. I have a sentinel m16 clone with a nimbus clone. I like it enough but its time for me to upgrade. I am looking to get the JA mod. the JA mod comes with copper contact pins. I really want to find a way to buy silver or brass contact pins. I really want all 3 so I can experiment with which one produces the most vapor. Can anyone help me out with where to buy contact pins or which ones are the best???