diff --git a/netbox/dcim/models/racks.py b/netbox/dcim/models/racks.py
index d86fc3af2..9e3efc3a9 100644
--- a/netbox/dcim/models/racks.py
+++ b/netbox/dcim/models/racks.py
@@ -180,7 +180,7 @@ class RackType(RackBase):
 
         # Validate outer dimensions and unit
         if any([self.outer_width, self.outer_depth, self.outer_height]) and not self.outer_unit:
-            raise ValidationError(_("Must specify a unit when setting an outer width/depth/height"))
+            raise ValidationError(_("Must specify a unit when setting an outer dimension"))
 
         # Validate max_weight and weight_unit
         if self.max_weight and not self.weight_unit: