diff --git a/src/asn1_types/end_of_content.rs b/src/asn1_types/end_of_content.rs
index 4a9d291..c82c961 100644
--- a/src/asn1_types/end_of_content.rs
+++ b/src/asn1_types/end_of_content.rs
@@ -10,6 +10,12 @@ use core::convert::TryFrom;
 #[derive(Debug)]
 pub struct EndOfContent {}
 
+impl Default for EndOfContent {
+    fn default() -> Self {
+        Self::new()
+    }
+}
+
 impl EndOfContent {
     pub const fn new() -> Self {
         EndOfContent {}
diff --git a/src/asn1_types/null.rs b/src/asn1_types/null.rs
index ba9f0f5..a7fd587 100644
--- a/src/asn1_types/null.rs
+++ b/src/asn1_types/null.rs
@@ -5,6 +5,12 @@ use core::convert::TryFrom;
 #[derive(Debug, PartialEq, Eq)]
 pub struct Null {}
 
+impl Default for Null {
+    fn default() -> Self {
+        Self::new()
+    }
+}
+
 impl Null {
     pub const fn new() -> Self {
         Null {}
diff --git a/src/asn1_types/oid.rs b/src/asn1_types/oid.rs
index aa8bc43..a119348 100644
--- a/src/asn1_types/oid.rs
+++ b/src/asn1_types/oid.rs
@@ -245,9 +245,7 @@ impl<'a> Oid<'a> {
 
     /// Return an iterator over the sub-identifiers (arcs).
     /// Returns `None` if at least one arc does not fit into `u64`.
-    pub fn iter(
-        &'_ self,
-    ) -> Option<impl Iterator<Item = u64> + FusedIterator + ExactSizeIterator + '_> {
+    pub fn iter(&'_ self) -> Option<impl FusedIterator<Item = u64> + ExactSizeIterator + '_> {
         // Check that every arc fits into u64
         let bytes = if self.relative {
             &self.asn1
diff --git a/src/asn1_types/tagged/builder.rs b/src/asn1_types/tagged/builder.rs
index 093b9d9..1711413 100644
--- a/src/asn1_types/tagged/builder.rs
+++ b/src/asn1_types/tagged/builder.rs
@@ -29,6 +29,12 @@ pub struct TaggedParserBuilder<TagKind, E = Error> {
     _e: PhantomData<E>,
 }
 
+impl<TagKind, E> Default for TaggedParserBuilder<TagKind, E> {
+    fn default() -> Self {
+        Self::new()
+    }
+}
+
 impl<TagKind, E> TaggedParserBuilder<TagKind, E> {
     /// Create a default `TaggedParserBuilder` builder
     ///