diff --git a/src/Crypto/AbstractKeypair.php b/src/Crypto/AbstractKeypair.php
index 5298978b..d0568faf 100644
--- a/src/Crypto/AbstractKeypair.php
+++ b/src/Crypto/AbstractKeypair.php
@@ -11,7 +11,7 @@
 
 abstract class AbstractKeypair
 {
-    protected const CURVE = '';
+    public const CURVE = '';
 
     public const ALG = '';
 
diff --git a/src/Crypto/DidKey.php b/src/Crypto/DidKey.php
index 2f38445b..f3902804 100644
--- a/src/Crypto/DidKey.php
+++ b/src/Crypto/DidKey.php
@@ -7,7 +7,6 @@
 use Mdanter\Ecc\Crypto\Key\PublicKey;
 use Mdanter\Ecc\Crypto\Key\PublicKeyInterface;
 use Mdanter\Ecc\Curves\CurveFactory;
-use Mdanter\Ecc\Curves\SecgCurve;
 use Mdanter\Ecc\EccFactory;
 use Mdanter\Ecc\Serializer\Point\CompressedPointSerializer;
 use Mdanter\Ecc\Serializer\PublicKey\DerPublicKeySerializer;
@@ -27,13 +26,9 @@ class DidKey
 {
     protected const DID_KEY_PREFIX = 'did:key:';
 
-    protected const P256_DID_PREFIX = [0x80, 0x24];
-
-    protected const SECP256K1_DID_PREFIX = [0xe7, 0x01];
-
     protected const ALGS = [
-        'ES256' => SecgCurve::NAME_SECP_256R1,
-        'ES256K' => SecgCurve::NAME_SECP_256K1,
+        P256Keypair::ALG => P256Keypair::CURVE,
+        K256Keypair::ALG => K256Keypair::CURVE,
     ];
 
     /**
@@ -55,8 +50,8 @@ public static function parse(string $didkey): array
         $alg_prefix = substr($keyBytes, offset: 0, length: 2);
 
         $alg = match ($alg_prefix) {
-            self::p256prefix() => 'ES256',
-            self::k256prefix() => 'ES256K',
+            P256Keypair::MULTIBASE_PREFIX => P256Keypair::ALG,
+            K256Keypair::MULTIBASE_PREFIX => K256Keypair::ALG,
             default => throw new InvalidArgumentException('Unsupported format.'),
         };
 
@@ -85,7 +80,7 @@ public static function parse(string $didkey): array
 
         return [
             'alg' => $alg,
-            'key' => $pem
+            'key' => $pem,
         ];
     }
 
@@ -103,8 +98,8 @@ public static function encode(PublicKeyInterface $pubkey): string
         $compressed = $serializer->serialize($pubkey->getPoint());
 
         $prefix = match ($pubkey->getCurve()->getName()) {
-            SecgCurve::NAME_SECP_256R1 => self::p256prefix(),
-            SecgCurve::NAME_SECP_256K1 => self::k256prefix(),
+            P256Keypair::CURVE => P256Keypair::MULTIBASE_PREFIX,
+            K256Keypair::CURVE => K256Keypair::MULTIBASE_PREFIX,
         };
 
         return Multibase::encode(Multibase::BASE58BTC, $prefix.hex2bin($compressed));
@@ -117,14 +112,4 @@ public static function format(PublicKeyInterface $pubkey): string
     {
         return self::DID_KEY_PREFIX.self::encode($pubkey);
     }
-
-    protected static function k256prefix(): string
-    {
-        return collect(self::SECP256K1_DID_PREFIX)->implode(fn ($value) => chr($value), '');
-    }
-
-    protected static function p256prefix(): string
-    {
-        return collect(self::P256_DID_PREFIX)->implode(fn ($value) => chr($value), '');
-    }
 }
diff --git a/src/Crypto/K256Keypair.php b/src/Crypto/K256Keypair.php
index cf9832f4..a17efe6c 100644
--- a/src/Crypto/K256Keypair.php
+++ b/src/Crypto/K256Keypair.php
@@ -4,7 +4,9 @@
 
 class K256Keypair extends AbstractKeypair
 {
-    protected const CURVE = 'secp256k1';
+    public const CURVE = 'secp256k1';
 
     public const ALG = 'ES256K';
+
+    public const MULTIBASE_PREFIX = "\xe7\x01";
 }
diff --git a/src/Crypto/P256Keypair.php b/src/Crypto/P256Keypair.php
index 8b498ec2..b7053b6e 100644
--- a/src/Crypto/P256Keypair.php
+++ b/src/Crypto/P256Keypair.php
@@ -4,7 +4,9 @@
 
 class P256Keypair extends AbstractKeypair
 {
-    protected const CURVE = 'secp256r1';
+    public const CURVE = 'secp256r1';
 
     public const ALG = 'ES256';
+
+    public const MULTIBASE_PREFIX = "\x80\x24";
 }