I have a Stihl HS45 hedge trimmer, which oil do u recommend I use, ultra or ordinary 2 stroke oil?

Just the normal 2 stroke will be fine: https://www.lsengineers.co.uk/catalog/product/view/id/9245 https://www.lsengineers.co.uk/stihl-2-stroke-oil-1ltr-with-measure.html