The
line of the upper arm is parallel to a
similar line running from the top left hand corner to a golden section point measured
along the bottom from the left.
From the back, it looks quite
similar to the R11, but the antenna
lines seem to have received a bit of a refresh - instead of two thin
lines (like R11), the R11 - S comes with a thicker single antenna
line running along the top and the bottom.