diff --git a/DDRec/src/plugins/addVariantParameters.cpp b/DDRec/src/plugins/addVariantParameters.cpp
index 3f5a517b3e515c80ed727d7f1a6e299ea85fee99..f5ce3e7ed4deb4353da0a0b2a6fbb4056e146380 100644
--- a/DDRec/src/plugins/addVariantParameters.cpp
+++ b/DDRec/src/plugins/addVariantParameters.cpp
@@ -89,7 +89,7 @@ static long addVariantParameters(Detector& description, int argc, char** argv) {
       extension->variantParameters[key] = value;
     }
     else if (type == "double") {
-      extension->variantParameters[key] = dd4hep:_toDouble(value);
+      extension->variantParameters[key] = dd4hep::_toDouble(value);
     }
     else if (type == "int") {
       extension->variantParameters[key] = dd4hep::_toInt(value);