Here is how a lightning link works. There are less than 500 registered transferrable lightning links in the US. They work for virtually all calibers that are available for AR15s.
Attention ATF boozos: AInt the 1st and 2nd amendments GREAT!!
OK, I'll pick up an AR tomorrow. It'll be fully auto by Saturday evening? Cmon!! Is that really all there is to it? A piece of dental floss will work for two maybe three clips!! I'll let you know when the SKS is fully auto!!.