Deployed: 4 cm (from top of rail to top of diopter ring)
Folded: 1,5 cm (from top of rail to top of windage adjustment screw, the highest point when folded down)
It is for use with the 33mm folding front sight.
If you haven' gotten it yet, I would tell you to save your money and buy something else.....it comes off very easy, and the adjustments are very crude. The values we use are:
Elevation adjustment, 1 click:
30m = 1,2cm
100m = 4cm
200m = 8cm
300m = 12cm
Windage adjustment, 1 click:
30m = 0,9cm
100m = 3cm
200m = 6cm
300m = 9cm