From the Rulebook:
This Ability is not magical in nature. It could represent poison from a vial or using a piece of twine to fix a broken arrow.
An Ability listed as (ex) which is defined as being an Enchantment in its Ability definition generally behaves as an Enchantment but does not count towards the limit of Enchantments that may be worn by a player or count for the purposes of Attuned, Essence Graft or similar magic and abilities.
Incantations for Abilities listed as Extraordinary (ex) do not require a free hand.