diff --git a/drone/config/spec/configspec_client.ini b/drone/config/spec/configspec_client.ini
index 0287009..8666ed1 100644
--- a/drone/config/spec/configspec_client.ini
+++ b/drone/config/spec/configspec_client.ini
@@ -40,7 +40,10 @@ rotation = float_list(default=list(0.0, 0.0, 0.0), min=3, max=3)
 [GPS FRAME]
 lat = string(default=0)
 lon = string(default=0)
+# Clockwise yaw rotation from North direction in degrees
 yaw = float(default=0)
+# AMSL height of frame. Available options: "current" of float value in meters.
+amsl = string(default=current)
 
 [ANIMATION]
 # Available options: