The newer STD framing is much the same as the UL, 3-piece consisting of an ULE, LLE and an extension piece in the middle housing both ferrules I call an MLE (Emily).
It does away with annoying wing tip extensions and simplifies spar replacement since the MLE has both ferrules set in it.
SUL has a 2-piece LE, a longer ULE (with ferrule) and a normal length LLE.
The Vent still retains wing tip extensions because I add weights to them.
Hmmm.. Tech sections are somewhat out of date
Hope that helps.