diff --git a/src/gwproto/named_types/dfr_config.py b/src/gwproto/named_types/dfr_config.py
index e2800d92..0e8389db 100644
--- a/src/gwproto/named_types/dfr_config.py
+++ b/src/gwproto/named_types/dfr_config.py
@@ -2,13 +2,13 @@
 
 from typing import Literal
 
-from pydantic import PositiveInt
+from pydantic import PositiveInt, StrictInt
 
 from gwproto.named_types.channel_config import ChannelConfig
 
 
 class DfrConfig(ChannelConfig):
     OutputIdx: PositiveInt
-    InitialVoltsTimes100: PositiveInt
+    InitialVoltsTimes100: StrictInt
     TypeName: Literal["dfr.config"] = "dfr.config"
     Version: Literal["000"] = "000"