diff --git a/README.md b/README.md
index 9b0f8a1..f9504f7 100644
--- a/README.md
+++ b/README.md
@@ -124,6 +124,8 @@ Supported PKI encryption types:
 | piv-p256         | ECDH(secp256r1) | PIV Slot (Previous `ecdh`)              |
 | piv-p384         | ECDH(secp384r1) | PIV Slot (Previous `ecdh-p384`)         |
 | key-p256         | ECDH(secp256r1) | Key Stored in macOS Secure Enclave      |
+| ext-p256         | ECDH(secp256r1) | Key Protected by External Command       |
+| ext-p384         | ECDH(secp384r1) | Key Protected by External Command       |
 | piv-rsa          | PKCS1-v1.5      | PIV Slot                                |
 
 Smart Card(Yubikey) protected ECDH Encryption description as below: