diff --git a/bitcoin/core/script.py b/bitcoin/core/script.py
index 581a0b4e..9deb827c 100644
--- a/bitcoin/core/script.py
+++ b/bitcoin/core/script.py
@@ -230,6 +230,7 @@ def __new__(cls, n):
 # expansion
 OP_NOP1 = CScriptOp(0xb0)
 OP_NOP2 = CScriptOp(0xb1)
+OP_CHECKLOCKTIMEVERIFY = OP_NOP2
 OP_NOP3 = CScriptOp(0xb2)
 OP_NOP4 = CScriptOp(0xb3)
 OP_NOP5 = CScriptOp(0xb4)
@@ -351,6 +352,7 @@ def __new__(cls, n):
     OP_CHECKMULTISIGVERIFY: 'OP_CHECKMULTISIGVERIFY',
     OP_NOP1: 'OP_NOP1',
     OP_NOP2: 'OP_NOP2',
+    OP_CHECKLOCKTIMEVERIFY: 'OP_CHECKLOCKTIMEVERIFY',
     OP_NOP3: 'OP_NOP3',
     OP_NOP4: 'OP_NOP4',
     OP_NOP5: 'OP_NOP5',
@@ -470,6 +472,7 @@ def __new__(cls, n):
     'OP_CHECKMULTISIGVERIFY': OP_CHECKMULTISIGVERIFY,
     'OP_NOP1': OP_NOP1,
     'OP_NOP2': OP_NOP2,
+    'OP_CHECKLOCKTIMEVERIFY': OP_CHECKLOCKTIMEVERIFY,
     'OP_NOP3': OP_NOP3,
     'OP_NOP4': OP_NOP4,
     'OP_NOP5': OP_NOP5,
@@ -1030,6 +1033,7 @@ def SignatureHash(script, txTo, inIdx, hashtype):
         'OP_CHECKMULTISIGVERIFY',
         'OP_NOP1',
         'OP_NOP2',
+        'OP_CHECKLOCKTIMEVERIFY',
         'OP_NOP3',
         'OP_NOP4',
         'OP_NOP5',
@@ -1061,4 +1065,4 @@ def SignatureHash(script, txTo, inIdx, hashtype):
         'RawSignatureHash',
         'SignatureHash',
         'IsLowDERSignature',
-)
+)
\ No newline at end of file