can you help me about the meaning of "sif window" choices?

1)Reinforced
ok: example is pipe to pipe with reinforcing plate

2)Unreiforced
ok: example is pipe to pipe without reinforcing plate

3)Welding
ok: the "classic" Tee fitting

4)Sweepolet
ok: the sweepolet

5)Weldolet
ok: the weldolet

6)Extruded
???

7)Butt weld
???

8)Socket
for tee socket weld?

9)socket/unfinn
???

10)Tapered
???

11)Threaded
For tee threaded???

12)Dbl Welded
???

13)Lap joint
ok: for lap joint flanges

14)BF Latrolet
Is this for latrolet? what's "BF" for?

16)BF Ins Wld
???

17)Full encirclement
???