diff --git a/src/handler.rs b/src/handler.rs
index 4e75a10..16bc12b 100644
--- a/src/handler.rs
+++ b/src/handler.rs
@@ -54,29 +54,6 @@ impl<T> Service<T> for Sink {
     }
 }
 
-/// [`Event`]と`State`の直積です。
-///
-/// [`Event`]: crate::Event
-#[must_use]
-#[derive(Debug, Clone)]
-pub struct EventWithState<State> {
-    state: State,
-    event: Event,
-}
-
-impl<State> From<(State, Event)> for EventWithState<State> {
-    fn from((state, event): (State, Event)) -> Self {
-        Self { state, event }
-    }
-}
-
-impl<State> From<EventWithState<State>> for (State, Event) {
-    fn from(value: EventWithState<State>) -> Self {
-        let EventWithState { state, event } = value;
-        (state, event)
-    }
-}
-
 /// 内部の`Service`に`State`を渡す[`Service`]です。
 ///
 /// `WithState::call`の度に`State`がcloneされるため、`State`は[`Clone`]を実装する必要があります。
@@ -92,44 +69,38 @@ pub struct WithState<State, Service> {
 
 impl<State, Srv> Service<Event> for WithState<State, Srv>
 where
-    Srv: Service<EventWithState<State>>,
+    Srv: Service<(State, Event)>,
     State: Clone,
 {
     type Response = Srv::Response;
     type Error = Srv::Error;
     type Future = Srv::Future;
 
-    fn poll_ready(&mut self, _cx: &mut Context<'_>) -> Poll<Result<(), Self::Error>> {
-        Poll::Ready(Ok(()))
+    fn poll_ready(&mut self, cx: &mut Context<'_>) -> Poll<Result<(), Self::Error>> {
+        self.service.poll_ready(cx)
     }
 
     fn call(&mut self, request: Event) -> Self::Future {
-        let request = EventWithState {
-            state: self.state.clone(),
-            event: request,
-        };
+        let request = (self.state.clone(), request);
         self.service.call(request)
     }
 }
 
-impl<OState, State, Srv> Service<EventWithState<OState>> for WithState<State, Srv>
+impl<OState, State, Srv> Service<(OState, Event)> for WithState<State, Srv>
 where
-    Srv: Service<EventWithState<State>>,
+    Srv: Service<(State, Event)>,
     State: Clone,
 {
     type Response = Srv::Response;
     type Error = Srv::Error;
     type Future = Srv::Future;
 
-    fn poll_ready(&mut self, _cx: &mut Context<'_>) -> Poll<Result<(), Self::Error>> {
-        Poll::Ready(Ok(()))
+    fn poll_ready(&mut self, cx: &mut Context<'_>) -> Poll<Result<(), Self::Error>> {
+        self.service.poll_ready(cx)
     }
 
-    fn call(&mut self, request: EventWithState<OState>) -> Self::Future {
-        let request = EventWithState {
-            state: self.state.clone(),
-            event: request.event,
-        };
+    fn call(&mut self, (_, request): (OState, Event)) -> Self::Future {
+        let request = (self.state.clone(), request);
         self.service.call(request)
     }
 }
diff --git a/src/macros.rs b/src/macros.rs
index d0df7e4..cc47f55 100644
--- a/src/macros.rs
+++ b/src/macros.rs
@@ -426,8 +426,8 @@ macro_rules! event_service_call {
         $s:ident;
         $v:ident ( $i:ident ) => $e:expr
     ) => {
-        fn call(&mut self, req: $crate::handler::EventWithState<State>) -> Self::Future {
-            let ($s, event) = req.into();
+        fn call(&mut self, req: (State, $crate::handler::Event)) -> Self::Future {
+            let ($s, event) = req;
             match event {
                 $crate::Event::$v($i) => ::futures::future::Either::Left(
                     $crate::handler::WrapErrorFuture::new(self.inner.call($e)),
@@ -472,14 +472,14 @@ macro_rules! event_service {
             $crate::macros::event_service_call! { [< $e:camel >] (e) }
         }
 
-        impl<State, Service, Fallback> ::tower::Service<$crate::handler::EventWithState<State>>
+        impl<State, Service, Fallback> ::tower::Service<(State, $crate::handler::Event)>
         for [< $e:camel Service >] <Service, Fallback, $crate::payloads::[< $e:camel Payload >] >
         where
             Service: ::tower::Service<$crate::payloads::[< $e:camel Payload >], Response = ()>,
             Service::Error: ::std::convert::Into<::std::boxed::Box<
                 dyn ::std::error::Error + ::std::marker::Send + ::std::marker::Sync + 'static,
             >>,
-            Fallback: ::tower::Service<$crate::handler::EventWithState<State>, Response = ()>,
+            Fallback: ::tower::Service<(State, $crate::handler::Event), Response = ()>,
             Fallback::Error: ::std::convert::Into<::std::boxed::Box<
                 dyn ::std::error::Error + ::std::marker::Send + ::std::marker::Sync + 'static,
             >>,
@@ -489,7 +489,7 @@ macro_rules! event_service {
             $crate::macros::event_service_call! { state; [< $e:camel >] (e) => e }
         }
 
-        impl<State, Service, Fallback> ::tower::Service<$crate::handler::EventWithState<State>>
+        impl<State, Service, Fallback> ::tower::Service<(State, $crate::handler::Event)>
         for [< $e:camel Service >] <Service, Fallback, ($crate::payloads::[< $e:camel Payload >],) >
         where
             Service: ::tower::Service<
@@ -499,7 +499,7 @@ macro_rules! event_service {
             Service::Error: ::std::convert::Into<::std::boxed::Box<
                 dyn ::std::error::Error + ::std::marker::Send + ::std::marker::Sync + 'static,
             >>,
-            Fallback: ::tower::Service<$crate::handler::EventWithState<State>, Response = ()>,
+            Fallback: ::tower::Service<(State, $crate::handler::Event), Response = ()>,
             Fallback::Error: ::std::convert::Into<::std::boxed::Box<
                 dyn ::std::error::Error + ::std::marker::Send + ::std::marker::Sync + 'static,
             >>,
@@ -509,7 +509,7 @@ macro_rules! event_service {
             $crate::macros::event_service_call! { state; [< $e:camel >] (e) => (e,) }
         }
 
-        impl<State, Service, Fallback> ::tower::Service<$crate::handler::EventWithState<State>>
+        impl<State, Service, Fallback> ::tower::Service<(State, $crate::handler::Event)>
         for [< $e:camel Service >] <Service, Fallback, (State, $crate::payloads::[< $e:camel Payload >] )>
         where
             Service: ::tower::Service<
@@ -519,7 +519,7 @@ macro_rules! event_service {
             Service::Error: ::std::convert::Into<::std::boxed::Box<
                 dyn ::std::error::Error + ::std::marker::Send + ::std::marker::Sync + 'static,
             >>,
-            Fallback: ::tower::Service<$crate::handler::EventWithState<State>, Response = ()>,
+            Fallback: ::tower::Service<(State, $crate::handler::Event), Response = ()>,
             Fallback::Error: ::std::convert::Into<::std::boxed::Box<
                 dyn ::std::error::Error + ::std::marker::Send + ::std::marker::Sync + 'static,
             >>,