Newcon Optik 7x50 AN Binoculars with Compass and Reticle - Manual (Page 9)

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The light from the object or target you are looking at
enters the binoculars through the objective lens system (1,
Fig. 1). Due to the objective lens, the image at this point
is turned upside down. However, as the image passes
through the prism system, (known as the erective prisms)
(2, Fig. 1) it becomes right side up (erect) and changed
from right to left, to left to right. After the prisms the
image rays pass through the reticle lens (3, Fig. 1) and
then through the eyepiece (4, Fig. 1).
3.2 Reticle
Reticle lens (3, Fig. 1) contains vertical and horizontal
lines that constitute an M22 reticle. Though reticle scales
may form a cross or upside down T (Fig. 2, A, B, C) they
share the same scale division value: each small division
on both vertical and horizontal lines is 5 mils and each big
division is 10 mils (360º equals 6400 mils).