I saw on SB tactical website a few pictures of a Sig brace that looks its styled after a HK UMP's rear stock appears to fold with same hinge as well... However all i saw was just two pictures and i cant seem to find any addition information about product.. has anyone seen this stock and know anything more about it? seems they have quite a few new braces in the works or have recently released... Reason i ask is i just got my HK53k back and im looking to see what's available until i can SBR her