With infinite skill I totally mangled the spring on the 30 Bolt Pencil Kit I was putting together. Could not find the proper replacement spring for sale (my fault, my dime). So, I contacted PSI and after a minor amount of hoop-jumping, they sent me out a replacement spring. I know there have been some negative (Jeers) at this vendor, but for me, they came through and is still my primary vendor. So, thanks PSI.