Hey guys Ive been Googling for hours to try to find out the actual type of rear night sight on my sig stx. Can't find it! Let me clarify exactly what I mean here.....the small line directly under the notch. This is the only gun I have ever seen with this kind of rear night sight. I know the sights are classified at Patridge sights but was curious to know if there's an actual name for the line under the notch. I don't know why this is bugging me so much but I cannot find anything about them. Anyone else seen these sights before?