There has been a lot of questions asked recently about having more than one short upper, but only one registered SBR lower. The questions have been whether or not it would be illegal (constructive posession) to own more than one short upper but only one SBR lower and one or more non-SBR lowers. On another site, a user posted a letter and the response from BATFE's NFA branch addressing this issue. I thought users here at TFL would get some useful information from it, so here are the scans...