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+---
+title: "Legacy armhole depth"
+---
+
+This option allows you to use the legacy way of calculating the armhole depth in Brian, which Carlton extends.
+
+The legacy (v2) way used the biceps circumference to estimate the armhole depth.
+
+The v3 way instead uses the waist to armpit measurement to locate the bottom of the armhole.
+
+If you enable this option, the Brian block will revert to the v2 way of calculating the armhole depth, and Carlton will follow.