Tile adhesive classification

Tile adhesive classification

There are many adhesives and they are classified with a number code that represents different properties of the adhesive. Typically this number looks like C2TEFS1. What does it mean:
C - means that it is cement based adhesive (alternatives are D - ready mixed, or R - resin (epoxy))
No. 2 means that it is an adhesive with improved adhesion, while no 1 means that it is standard adhesive
T - means that the adhesive has reduced slip, it is slip resistant - that is better for wall tiles
E - means extended working time, does not dry too quicly, while
F - means that it dries faster.

Last letter is always connected with number and is related to flexibility:
S1 = Deformable (Flexible)
S2 = Highly Deformable