WordPress at a glance
filter is not described

woocommerce_order_amount_item_tax filter-hook . WC 1.0

Usage

add_filter( 'woocommerce_order_amount_item_tax', 'filter_function_name_5313', 10, 4 );
function filter_function_name_5313( $tax, $item, $round, $that ){
	// filter...

	return $tax;
}
$tax
-
$item
-
$round
-
$that
-

Where the hook is called

WC_Abstract_Order::get_item_tax()
woocommerce_order_amount_item_tax
woocommerce/includes/abstracts/abstract-wc-order.php 1864
return apply_filters( 'woocommerce_order_amount_item_tax', $tax, $item, $round, $this );

Where in WP core the hook is used WooCommerce

Usage not found.