Read from the World of Warcraft client build files.
How Crimsonscale Helm Compares
Who It Suits
Mail is the armor type Evoker, Hunter and Shaman wear. With Agility or Intellect, Crimsonscale Helm suits Beast Mastery, Marksmanship and Survival Hunter; Elemental, Enhancement and Restoration Shaman; Devastation, Preservation and Augmentation Evoker.
Transmog Sets
Crimsonscale Helm is part of the transmog set Jade Guardian's Regalia (Hunter, Shaman and Evoker only). The other 16 pieces:
Built from the World of Warcraft client build files and recorded Auction House snapshots.
Where Crimsonscale Helm Fits
Other Items Named Crimsonscale Helm
2 other items in the current build are also called Crimsonscale Helm. Same-name entries are usually a different rank, faction, quest stage or reward track of the same object.
Blizzard numbers items as they are created, so the named items next to ID 101931 (101926 to 101936) were usually added in the same batch as Crimsonscale Helm: the same quest line, zone, vendor or reward set.