how does "mod crit type on hitgroup" work.

[nameme1moretime]

like what does the attribute line have to look like, cause i want the head shots to work.
XCR.txt

[nosoop]

The value line in this CW3 config has an example:

"mod crit type on hitgroup"
{
	"plugin"	"custom-attribute-adapter/mod_crit_type_on_hitgroup"
	"value"		"hitgroup=1 crit_type=2"
}

[nameme1moretime]

thanks