diff --git a/src/asymmetric_crypto/curve25519.rs b/src/asymmetric_crypto/curve25519.rs
index f3efb4a..44a6cd6 100644
--- a/src/asymmetric_crypto/curve25519.rs
+++ b/src/asymmetric_crypto/curve25519.rs
@@ -34,14 +34,6 @@ pub const X25519_PK_LENGTH: usize = 32;
 pub struct X25519PrivateKey(Scalar);
 
 impl X25519PrivateKey {
-    /// Generate a new private key.
-    #[must_use]
-    pub fn new<R: RngCore + CryptoRng>(rng: &mut R) -> Self {
-        let mut bytes = [0; 64];
-        rng.fill_bytes(&mut bytes);
-        Self(Scalar::from_bytes_mod_order_wide(&bytes))
-    }
-
     /// Convert to bytes without copy.
     #[inline]
     #[must_use]
@@ -58,6 +50,14 @@ impl X25519PrivateKey {
 }
 
 impl KeyTrait<X25519_SK_LENGTH> for X25519PrivateKey {
+    /// Generate a new random key.
+    #[inline]
+    fn new<R: RngCore + CryptoRng>(rng: &mut R) -> Self {
+        let mut bytes = [0; 64];
+        rng.fill_bytes(&mut bytes);
+        Self(Scalar::from_bytes_mod_order_wide(&bytes))
+    }
+
     /// Converts the given key into bytes.
     #[inline]
     fn to_bytes(&self) -> [u8; Self::LENGTH] {
@@ -228,18 +228,15 @@ impl ZeroizeOnDrop for X25519PrivateKey {}
 #[serde(try_from = "&[u8]", into = "[u8; 32]")]
 pub struct X25519PublicKey(RistrettoPoint);
 
-impl X25519PublicKey {
+impl KeyTrait<X25519_PK_LENGTH> for X25519PublicKey {
     /// Generate a new random public key.
     #[inline]
-    #[must_use]
-    pub fn new<R: RngCore + CryptoRng>(rng: &mut R) -> Self {
+    fn new<R: RngCore + CryptoRng>(rng: &mut R) -> Self {
         let mut uniform_bytes = [0u8; 64];
         rng.fill_bytes(&mut uniform_bytes);
         Self(RistrettoPoint::from_uniform_bytes(&uniform_bytes))
     }
-}
 
-impl KeyTrait<X25519_PK_LENGTH> for X25519PublicKey {
     /// Converts the given public key into an array of bytes.
     #[inline]
     fn to_bytes(&self) -> [u8; Self::LENGTH] {
diff --git a/src/asymmetric_crypto/mod.rs b/src/asymmetric_crypto/mod.rs
index b6195f5..a37c834 100644
--- a/src/asymmetric_crypto/mod.rs
+++ b/src/asymmetric_crypto/mod.rs
@@ -1,7 +1,7 @@
 use crate::KeyTrait;
 use core::{
     fmt::Debug,
-    ops::{Add, Mul},
+    ops::{Add, Mul, Sub},
 };
 use rand_core::{CryptoRng, RngCore};
 use zeroize::{Zeroize, ZeroizeOnDrop};
@@ -11,9 +11,21 @@ pub mod curve25519;
 pub trait DhKeyPair<'a, const PK_LENGTH: usize, const SK_LENGTH: usize>:
     Debug + PartialEq + Eq + Send + Sync + Sized + Clone + Zeroize + ZeroizeOnDrop
 where
-    Self::PublicKey: Add + Mul<&'a Self::PrivateKey, Output = Self::PublicKey>,
-    Self::PrivateKey: 'a + Add,
+    Self::PublicKey:
+        Add + Mul<&'a Self::PrivateKey, Output = Self::PublicKey> + From<&'a Self::PrivateKey>,
+    Self::PrivateKey: 'a,
+    &'a Self::PrivateKey: Add<Output = Self::PrivateKey>
+        + Sub<Output = Self::PrivateKey>
+        + Mul<Output = Self::PrivateKey>,
 {
+    /// This is needed to be able to use `{ MyKeyPair::PK_LENGTH }`
+    /// as associated constant
+    const PK_LENGTH: usize = PK_LENGTH;
+
+    /// This is needed to be able to use `{ MyKeyPair::SK_LENGTH }`
+    /// as associated constant
+    const SK_LENGTH: usize = SK_LENGTH;
+
     /// Public key
     type PublicKey: KeyTrait<PK_LENGTH>;
 
diff --git a/src/lib.rs b/src/lib.rs
index 8e682aa..0ea39b0 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -18,6 +18,7 @@ pub mod entropy;
 pub mod kdf;
 pub mod symmetric_crypto;
 
+use rand_core::{RngCore, CryptoRng};
 use zeroize::{Zeroize, ZeroizeOnDrop};
 
 pub use crate::error::CryptoCoreError;
@@ -34,6 +35,10 @@ pub trait KeyTrait<const LENGTH: usize>:
     /// Key length
     const LENGTH: usize = LENGTH;
 
+    /// Generate a new random key.
+    #[must_use]
+    fn new<R: RngCore + CryptoRng>(rng: &mut R) -> Self;
+
     /// Convert the given key into a vector of bytes.
     #[must_use]
     fn to_bytes(&self) -> [u8; LENGTH];
diff --git a/src/symmetric_crypto/aes_256_gcm_pure/mod.rs b/src/symmetric_crypto/aes_256_gcm_pure/mod.rs
index fc7aed6..61f2d27 100644
--- a/src/symmetric_crypto/aes_256_gcm_pure/mod.rs
+++ b/src/symmetric_crypto/aes_256_gcm_pure/mod.rs
@@ -186,6 +186,7 @@ pub fn decrypt_in_place_detached(
 mod tests {
 
     use crate::{
+        KeyTrait,
         entropy::CsRng,
         symmetric_crypto::{
             aes_256_gcm_pure::{
diff --git a/src/symmetric_crypto/key.rs b/src/symmetric_crypto/key.rs
index 0be7c83..8fa29d5 100644
--- a/src/symmetric_crypto/key.rs
+++ b/src/symmetric_crypto/key.rs
@@ -11,16 +11,15 @@ use zeroize::{Zeroize, ZeroizeOnDrop};
 #[derive(Debug, Hash, Clone, PartialEq, Eq)]
 pub struct Key<const LENGTH: usize>([u8; LENGTH]);
 
-impl<const KEY_LENGTH: usize> Key<KEY_LENGTH> {
+impl<const LENGTH: usize> KeyTrait<LENGTH> for Key<LENGTH> {
     /// Generate a new symmetric random `Key`
-    pub fn new<R: RngCore + CryptoRng>(rng: &mut R) -> Self {
-        let mut key = [0; KEY_LENGTH];
+    #[inline]
+    fn new<R: RngCore + CryptoRng>(rng: &mut R) -> Self {
+        let mut key = [0; LENGTH];
         rng.fill_bytes(&mut key);
         Self(key)
     }
-}
 
-impl<const LENGTH: usize> KeyTrait<LENGTH> for Key<LENGTH> {
     /// Convert the given key into bytes.
     #[inline]
     fn to_bytes(&self) -> [u8; LENGTH] {
@@ -107,7 +106,7 @@ impl<const KEY_LENGTH: usize> Deref for Key<KEY_LENGTH> {
 #[cfg(test)]
 mod tests {
 
-    use crate::{entropy::CsRng, symmetric_crypto::key::Key};
+    use crate::{KeyTrait, entropy::CsRng, symmetric_crypto::key::Key};
     use core::ops::Deref;
 
     const KEY_LENGTH: usize = 32;