This is not seen often; a New Zealand Army Summer "bush shirt" issued in 1943 to troops in Italy, but it's United States made War Aid produce, using herringbone twill not Khaki Drill and made to a British type pattern with US made buttons.
I've included a photo of a 1943 New Zealand made Khaki Drill bush shirt issued only in the Pacific theatre.

NZ Khaki Summer Shirt, Italy Campaign, WW2NZ Khaki Summer Shirt, Italy Campaign, WW2NZ Khaki Summer Shirt, Italy Campaign, WW2NZ Khaki Summer Shirt, Italy Campaign, WW2NZ Khaki Summer Shirt, Italy Campaign, WW2