woocommerce_countries_estimated_for_prefix filter-hook . WC 1.0

Usage

add_filter( 'woocommerce_countries_estimated_for_prefix', 'filter_function_name_2354', 10, 2 );
function filter_function_name_2354( $return, $country_code ){
	// filter...

	return $return;
}

$return

-

$country_code

-

Where the hook is called

return apply_filters( 'woocommerce_countries_estimated_for_prefix', $return, $country_code );

Where in WP core the hook is used WooCommerce