diff --git a/gstreamer/src/caps_features.rs b/gstreamer/src/caps_features.rs
index d50bf101e..996123880 100644
--- a/gstreamer/src/caps_features.rs
+++ b/gstreamer/src/caps_features.rs
@@ -14,6 +14,7 @@ use glib::translate::*;
 use glib::StaticType;
 
 #[doc(alias = "GstCapsFeatures")]
+#[repr(transparent)]
 pub struct CapsFeatures(ptr::NonNull<ffi::GstCapsFeatures>);
 unsafe impl Send for CapsFeatures {}
 unsafe impl Sync for CapsFeatures {}
diff --git a/gstreamer/src/structure.rs b/gstreamer/src/structure.rs
index 668ee920f..a9bc183c6 100644
--- a/gstreamer/src/structure.rs
+++ b/gstreamer/src/structure.rs
@@ -63,6 +63,7 @@ impl GlibValueError for glib::value::ValueTypeMismatchOrNoneError {
 }
 
 #[doc(alias = "GstStructure")]
+#[repr(transparent)]
 pub struct Structure(ptr::NonNull<ffi::GstStructure>);
 unsafe impl Send for Structure {}
 unsafe impl Sync for Structure {}