diff --git a/nym-node/nym-node-metrics/src/prometheus_wrapper.rs b/nym-node/nym-node-metrics/src/prometheus_wrapper.rs
index e6c18c6f38..f634e7c644 100644
--- a/nym-node/nym-node-metrics/src/prometheus_wrapper.rs
+++ b/nym-node/nym-node-metrics/src/prometheus_wrapper.rs
@@ -419,7 +419,7 @@ mod tests {
         }
         .to_string();
         assert_eq!(
-            "nym_node_mixnet_ingress_packet_version_sphinx-42",
+            "nym_node_mixnet_ingress_packet_version_sphinx_42",
             parameterised
         );
     }