A qustion about "king's rock"

[13gh0st13]

Does it work with air slash and other flinching moves when they fail? I mean this:
after 'air slash' fails to cause flinch 'king's rock' effect activates and gives 10% chance o cause flinch anyway (20% with serene grace)
I got conflicting into on that from diffrent sources. It seems to work at least to some degree because bosses use Togekiss holding this item.
 

[Caennethi]

It's as the Bulba description for Gen 5 onwards says.

"Grants all attacking moves that do not already have a chance to flinch a 10% chance of causing each target to flinch."

So if a move does not have a chance to flinch it gives the move a 10% flinch chance.
This does not apply to moves like Air Slash that already have a chance to flinch.

[13gh0st13]

thank you