diff --git a/src/datasources/grafana.rs b/src/datasources/grafana.rs
index f4480a2..a9d5e70 100644
--- a/src/datasources/grafana.rs
+++ b/src/datasources/grafana.rs
@@ -118,7 +118,7 @@ impl Metric for Grafana {
         Ok(r)
     }
 
-    fn boxed_clone(&self) -> Box<dyn Metric + Sync> {
+    fn boxed_clone(&self) -> Box<dyn Metric + Sync + Send> {
         return Box::new(self.clone());
     }
 }
diff --git a/src/datasources/grafana/prometheus.rs b/src/datasources/grafana/prometheus.rs
index 5707537..86c60d6 100644
--- a/src/datasources/grafana/prometheus.rs
+++ b/src/datasources/grafana/prometheus.rs
@@ -63,7 +63,7 @@ impl Metric for Prometheus {
         return prometheus::parse_result(value);
     }
 
-    fn boxed_clone(&self) -> Box<dyn Metric + Sync> {
+    fn boxed_clone(&self) -> Box<dyn Metric + Sync + Send> {
         return Box::new(self.clone());
     }
 }
diff --git a/src/datasources/influx.rs b/src/datasources/influx.rs
index 5aad531..edb0149 100644
--- a/src/datasources/influx.rs
+++ b/src/datasources/influx.rs
@@ -90,7 +90,7 @@ impl Metric for Influx {
         return parse_result(value);
     }
 
-    fn boxed_clone(&self) -> Box<dyn Metric + Sync> {
+    fn boxed_clone(&self) -> Box<dyn Metric + Sync + Send> {
         return Box::new(self.clone());
     }
 }
diff --git a/src/datasources/prometheus.rs b/src/datasources/prometheus.rs
index 30a5fa7..b8ddd00 100644
--- a/src/datasources/prometheus.rs
+++ b/src/datasources/prometheus.rs
@@ -98,7 +98,7 @@ impl Metric for Prometheus {
         return parse_result(value);
     }
 
-    fn boxed_clone(&self) -> Box<dyn Metric + Sync> {
+    fn boxed_clone(&self) -> Box<dyn Metric + Sync + Send> {
         return Box::new(self.clone());
     }
 }
diff --git a/src/metric.rs b/src/metric.rs
index a1a1d59..f6c93fc 100644
--- a/src/metric.rs
+++ b/src/metric.rs
@@ -59,7 +59,7 @@ impl Default for MetricResult {
 #[async_trait]
 pub trait Metric {
 
-    fn boxed_clone(&self) -> Box<dyn Metric + Sync>;
+    fn boxed_clone(&self) -> Box<dyn Metric + Sync + Send>;
 
     // (to - from) / step < 10000
     async fn query_chunk(&self, from: u64, to: u64, step: u64) -> types::Result<MetricResult>;