diff --git a/src/futures.rs b/src/futures.rs
index 8100f7e..ee941d5 100644
--- a/src/futures.rs
+++ b/src/futures.rs
@@ -5,7 +5,7 @@ use futures_core::Stream;
 
 use crate::{SendWrapper, invalid_deref, invalid_poll};
 
-impl<F: Future> Future for SendWrapper<F> {
+impl<F: Future + ?Sized> Future for SendWrapper<F> {
     type Output = F::Output;
 
     /// Polls this [`SendWrapper`] [`Future`].
@@ -22,7 +22,7 @@ impl<F: Future> Future for SendWrapper<F> {
     }
 }
 
-impl<S: Stream> Stream for SendWrapper<S> {
+impl<S: Stream + ?Sized> Stream for SendWrapper<S> {
     type Item = S::Item;
 
     /// Polls this [`SendWrapper`] [`Stream`].
diff --git a/src/lib.rs b/src/lib.rs
index 4bbd63e..d489c00 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -122,9 +122,9 @@ cfg_if::cfg_if! {
 /// threads, as long as you access the contained value only from within the
 /// original thread and make sure that it is dropped from within the original
 /// thread.
-pub struct SendWrapper<T> {
-    data: ManuallyDrop<T>,
+pub struct SendWrapper<T: ?Sized> {
     thread_id: ThreadId,
+    data: ManuallyDrop<T>,
 }
 
 impl<T> SendWrapper<T> {
@@ -138,13 +138,6 @@ impl<T> SendWrapper<T> {
         }
     }
 
-    /// Returns `true` if the value can be safely accessed from within the
-    /// current thread.
-    #[inline]
-    pub fn valid(&self) -> bool {
-        self.thread_id == current_id()
-    }
-
     /// Takes the value out of the `SendWrapper<T>`.
     ///
     /// # Safety
@@ -178,6 +171,15 @@ impl<T> SendWrapper<T> {
             invalid_deref()
         }
     }
+}
+
+impl<T: ?Sized> SendWrapper<T> {
+    /// Returns `true` if the value can be safely accessed from within the
+    /// current thread.
+    #[inline]
+    pub fn valid(&self) -> bool {
+        self.thread_id == current_id()
+    }
 
     /// Returns a reference to the contained value.
     ///
@@ -270,10 +272,10 @@ impl<T> SendWrapper<T> {
     }
 }
 
-unsafe impl<T> Send for SendWrapper<T> {}
-unsafe impl<T> Sync for SendWrapper<T> {}
+unsafe impl<T: ?Sized> Send for SendWrapper<T> {}
+unsafe impl<T: ?Sized> Sync for SendWrapper<T> {}
 
-impl<T> Drop for SendWrapper<T> {
+impl<T: ?Sized> Drop for SendWrapper<T> {
     /// Drops the contained value.
     ///
     /// # Panics
@@ -309,7 +311,7 @@ impl<T> Drop for SendWrapper<T> {
     }
 }
 
-impl<T: fmt::Debug> fmt::Debug for SendWrapper<T> {
+impl<T: fmt::Debug + ?Sized> fmt::Debug for SendWrapper<T> {
     /// Formats the value using the given formatter.
     ///
     /// If the `SendWrapper<T>` is formatted from a different thread than the
@@ -319,7 +321,7 @@ impl<T: fmt::Debug> fmt::Debug for SendWrapper<T> {
     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
         let mut f = f.debug_struct("SendWrapper");
         if let Some(data) = self.get() {
-            f.field("data", data);
+            f.field("data", &data);
         } else {
             f.field("data", &"<invalid>");
         }