diff --git a/src/bloom/domain/vessel.py b/src/bloom/domain/vessel.py
index cfe690b4..f32792b4 100644
--- a/src/bloom/domain/vessel.py
+++ b/src/bloom/domain/vessel.py
@@ -21,4 +21,4 @@ class Vessel(BaseModel):
     home_port_id: Union[int, None] = None
     created_at: Union[datetime, None] = None
     updated_at: Union[datetime, None] = None
-    details: Union[str None] = None
+    details: Union[str, None] = None