For those interested in this gas block/front sight combo, I just read on Calguns that Kerbs is making a new batch available for purchase. If you want one, email them and get on the list.
I guess it's been offered once before for $90.
Link to Calguns thread: http://www.calguns.net/calgunforum/s...d.php?t=470945
Fool-proofing serves only one purpose: identify bigger fools.