Where is the L strut? (Photo)

The L strut refers to the shape of the septum after a septoplasty.  The septum is composed of cartilage and bone and separates the right and left nasal passageway.  It is also vital to support of the nose.  Part of the septum is common removed during the procedure, but a piece shaped like an "L" is left in the nose for support.  This piece is commonly refereed to as the "L strut".  The L strut is felt by pressing on the dorsum and pushing up on the columella.  If you did not have an L strut, you would have a very weak and collapsing nose.  I hope this helps.  

You will likely not be able to feel your L strut. Although, the outside of the nose just above the tip is actually part of the L strut. The soft part you feel underneath is below the L strut where cartilage has been removed.

You see it in the first picture that you posted.  You would feel it right behind your columella that can "wiggle" a bit. 

The L-strut is the portion of the septal cartilage that remains after a submucous resection of the deviated portions of the cartilaginous and bony nasal septum. It provide support to the tip of the nose as well as the nasal dorsum and columella. It is imperative to preserve the L–strut when performing a rhinoplasty to maintain support. Re-creating the L–strut is a big part of revision rhinoplasty in order to assure the persistent support of the nasal tip and dorsum.