Strut K Value for Cantilever

[HBKS]

Hello, I am working on a project using a piece of strut as a cantilevered column (P1001 C41). My question is whether to use K=2 or K=1.2 for cantilevered strut? When working with normal steel shapes, I would expect to use K=2 but when I look at all the various strut catalogs, I inevitably see K=1.2 being used in their examples for cantilevers and in AISI 100-2007, I see no references at all to K=2. Additionally, the strut catalogs have no reference to K=2 and the tables for each strut type only go from K=0.65 to K=2.

If K=2 is simply not used for strut and it tops out at K=1.2, does anyone know the reason for this?
From AISC 360:

From strut catalog:

 

[Retrograde]

That "load and support condition" table has nothing to do with K values.

If the top is restrained against rotation you can use K = 1.2. Otherwise it is K = 2.0.