No, 40x is the strongest objective - so 800 stated magnification is correct.  I was remembering that initially I thought I could see 600 x with those lenses, later more like 450, although accuracy is difficult because: (i) you can't use a slide - the lens won't go down far enough so you have to sellotape something to the microscope stage - which makes manipulation of the image difficult; (ii) manipulation of the image, pulling it through several screens from one edge to the other of the strip of wrapper became more difficult over the month I was observing because the image became more luminous at 800 and also part of the screen blurred, so that it became more difficult to find 'landmarks' in order to measure; (iii) you are also estimating the width of the screen within the cylinder, since you are attempting to establish the veracity of the magnification of the width of the lenses and what you are looking at (a screen within the cylinder? a magnified objective lens tube); even comparing the screen one sees repeatedly with circles of various sizes next to the microscope it is difficult to get a consistent estimation - ie, does the screen look to be 110 mm wide or 90 mm and is this consistent with the apparent magnification of objects within the screen when one compares them with the object itself, or would that suggest a larger or smaller screen?