diff --git a/ptr_meta/example.md b/ptr_meta/example.md
index 691d630..f446caa 100644
--- a/ptr_meta/example.md
+++ b/ptr_meta/example.md
@@ -8,7 +8,7 @@ assert_eq!(ptr_meta::metadata(slice), slice.len());
 
 // Make your own wide pointers from data pointers and metadata
 let bytes = [b'h', b'e', b'l', b'l', b'o'];
-let ptr = ptr_meta::from_raw_parts::<str>(bytes.as_ptr().cast(), 5);
+let ptr = ptr_meta::from_raw_parts::<str>(bytes.as_ptr(), 5);
 println!("{} world!", unsafe { &*ptr }); // prints "hello world!"
 
 // Derive Pointee on your own types
@@ -24,7 +24,7 @@ impl CoolStr {
     }
 }
 
-let ptr = ptr_meta::from_raw_parts::<CoolStr>(bytes.as_ptr().cast(), 5);
+let ptr = ptr_meta::from_raw_parts::<CoolStr>(bytes.as_ptr(), 5);
 let cool = unsafe { &*ptr };
 cool.print_cool(); // prints "😎 hello 😎"
 
@@ -43,7 +43,7 @@ impl Printable for i32 {
 let i32_vtable = ptr_meta::metadata(&0i32 as &dyn Printable);
 let one_hundred = 100i32;
 let printable = ptr_meta::from_raw_parts::<dyn Printable>(
-    (&one_hundred as *const i32).cast(),
+    (&one_hundred as *const i32),
     i32_vtable,
 );
 unsafe {
diff --git a/ptr_meta/src/lib.rs b/ptr_meta/src/lib.rs
index 7715f7e..4b887bf 100644
--- a/ptr_meta/src/lib.rs
+++ b/ptr_meta/src/lib.rs
@@ -167,6 +167,12 @@ unsafe impl Pointee for std::ffi::OsStr {
     type Metadata = usize;
 }
 
+/// Pointers to types implementing this trait alias are “thin”.
+///
+/// This includes statically-Sized types and extern types.
+pub trait Thin: Pointee<Metadata = ()> {}
+impl<T: Pointee<Metadata = ()>> Thin for T {}
+
 /// Returns the metadata of the given pointer.
 ///
 /// `*mut T`, `&T`, and `&mut T` can all be passed directly to this function as
@@ -227,7 +233,7 @@ pub const fn to_raw_parts_mut<T: Pointee + ?Sized>(
 /// [`slice::from_raw_parts`]: core::slice::from_raw_parts
 #[inline]
 pub const fn from_raw_parts<T: Pointee + ?Sized>(
-    data_address: *const (),
+    data_address: *const impl Thin,
     metadata: <T as Pointee>::Metadata,
 ) -> *const T {
     // SAFETY: Accessing the value from the `PtrRepr` union is safe since
@@ -236,7 +242,7 @@ pub const fn from_raw_parts<T: Pointee + ?Sized>(
     unsafe {
         PtrRepr {
             components: PtrComponents {
-                data_address,
+                data_address: data_address.cast(),
                 metadata,
             },
         }
@@ -249,7 +255,7 @@ pub const fn from_raw_parts<T: Pointee + ?Sized>(
 /// See [`from_raw_parts`] for more details.
 #[inline]
 pub const fn from_raw_parts_mut<T: Pointee + ?Sized>(
-    data_address: *mut (),
+    data_address: *mut impl Thin,
     metadata: <T as Pointee>::Metadata,
 ) -> *mut T {
     // SAFETY: Accessing the value from the `PtrRepr` union is safe since
@@ -258,7 +264,7 @@ pub const fn from_raw_parts_mut<T: Pointee + ?Sized>(
     unsafe {
         PtrRepr {
             components: PtrComponents {
-                data_address,
+                data_address: data_address.cast(),
                 metadata,
             },
         }