diff --git a/contracts/SCERC721Derivative.sol b/contracts/SCERC721Derivative.sol
index d945556..6112243 100644
--- a/contracts/SCERC721Derivative.sol
+++ b/contracts/SCERC721Derivative.sol
@@ -105,12 +105,12 @@ contract SCERC721Derivative is Derivative {
   }
 
   function _mint(address sender, BalanceProof memory proof) internal {
-    _checkNetwork(proof.input[42]);
-    _checkAttestor(proof.input[44]);
-    _checkThreshold(proof.input[45]);
+    _checkNetwork(proof.input[2]);
+    _checkAttestor(proof.input[5]);
+    _checkThreshold(proof.input[3]);
     _checkTokenAddress(proof);
     _checkProof(proof);
-    _mintWithNullifier(sender, proof.input[43]);
+    _mintWithNullifier(sender, proof.input[4]);
   }
 
   function _checkNetwork(uint256 _network) internal view {
@@ -125,16 +125,13 @@ contract SCERC721Derivative is Derivative {
     bytes memory tokenBytes = bytes(
       Strings.toHexString(uint256(uint160(originalContract)), 20)
     );
-    for (uint8 i = 0; i < 42; ) {
-      require(
-        uint8(proof.input[i]) == uint8(tokenBytes[i]),
-        "This ZK proof is not from the correct token contract"
-      );
-
-      unchecked {
-        ++i;
-      }
-    }
+    bytes memory contractBytes = bytes(
+      Strings.toHexString(uint256(uint160(proof.input[1])), 20)
+    );
+    require(
+      keccak256(tokenBytes) == keccak256(contractBytes),
+      "This ZK proof is not from the correct token contract"
+    );
   }
 
   function _checkProof(BalanceProof memory proof) internal view {
diff --git a/contracts/SCERC721Ledger.sol b/contracts/SCERC721Ledger.sol
index ecd1e8c..65068e9 100644
--- a/contracts/SCERC721Ledger.sol
+++ b/contracts/SCERC721Ledger.sol
@@ -60,6 +60,7 @@
 pragma solidity ^0.8.16;
 
 import "@openzeppelin/contracts/token/ERC721/extensions/IERC721Metadata.sol";
+import "@openzeppelin/contracts/utils/Strings.sol";
 import "./base/Ledger.sol";
 import "./SCERC721Derivative.sol";
 
@@ -97,8 +98,7 @@ contract SCERC721Ledger is Ledger {
    */
   function mint(BalanceProof memory proof) external virtual {
     (string memory originalString, address original) = _extractAddress(
-      proof.input,
-      0
+      proof.input[1]
     );
     // Check if derivative already exists
     if (!_checkDerivativeExistence(originalString)) {
@@ -143,22 +143,13 @@ contract SCERC721Ledger is Ledger {
   /**
    * @dev Returns address from input
    */
-  function _extractAddress(uint256[46] memory input, uint256 startIndex)
+  function _extractAddress(uint256 numAddress)
     internal
     pure
     returns (string memory, address)
   {
-    bytes memory result = new bytes(addressLength);
-    uint256 length = startIndex + addressLength;
-    for (uint256 i = startIndex; i < length; ) {
-      result[i] = bytes1(uint8(input[i]));
-
-      unchecked {
-        ++i;
-      }
-    }
-    string memory addressString = string(result);
-    return (addressString, _toAddress(addressString));
+    string memory addr = Strings.toHexString(uint256(uint160(numAddress)), 20);
+    return (addr, _toAddress(addr));
   }
 
   // Credit to: https://github.com/provable-things/ethereum-api
diff --git a/contracts/SCExternalERC721Ledger.sol b/contracts/SCExternalERC721Ledger.sol
index f081ffc..373cb6e 100644
--- a/contracts/SCExternalERC721Ledger.sol
+++ b/contracts/SCExternalERC721Ledger.sol
@@ -105,8 +105,7 @@ contract SCExternalERC721Ledger is SCERC721Ledger {
     bytes32 vs
   ) external {
     (string memory originalString, address original) = _extractAddress(
-      proof.input,
-      0
+      proof.input[1]
     );
     // Check if derivative already exists
     if (!_checkDerivativeExistence(originalString)) {
diff --git a/contracts/SCFarcasterDerivative.sol b/contracts/SCFarcasterDerivative.sol
index 58fa12a..61eb08a 100644
--- a/contracts/SCFarcasterDerivative.sol
+++ b/contracts/SCFarcasterDerivative.sol
@@ -109,7 +109,7 @@ contract SCFarcasterDerivative is Derivative {
     bytes memory farcasterBytes = bytes("farcaster");
     for (uint8 i = 1; i < 10; ) {
       require(
-        uint8(proof.input[i]) == uint8(farcasterBytes[i]),
+        uint8(proof.input[i]) == uint8(farcasterBytes[i - 1]),
         "This ZK proof is not from the farcaster"
       );
 
diff --git a/contracts/interfaces/IBalanceCheckerVerifier.sol b/contracts/interfaces/IBalanceCheckerVerifier.sol
index bd4270f..28d062f 100644
--- a/contracts/interfaces/IBalanceCheckerVerifier.sol
+++ b/contracts/interfaces/IBalanceCheckerVerifier.sol
@@ -64,6 +64,6 @@ interface IBalanceCheckerVerifier {
     uint256[2] memory a,
     uint256[2][2] memory b,
     uint256[2] memory c,
-    uint256[46] memory input
+    uint256[6] memory input
   ) external view returns (bool r);
 }
diff --git a/contracts/models/BalanceProof.sol b/contracts/models/BalanceProof.sol
index 3b3ea51..389f1f0 100644
--- a/contracts/models/BalanceProof.sol
+++ b/contracts/models/BalanceProof.sol
@@ -63,5 +63,5 @@ struct BalanceProof {
   uint256[2] a;
   uint256[2][2] b;
   uint256[2] c;
-  uint256[46] input;
+  uint256[6] input;
 }
diff --git a/test/ExternalSCERC721Ledger.ts b/test/ExternalSCERC721Ledger.ts
index b418a78..9340fb2 100644
--- a/test/ExternalSCERC721Ledger.ts
+++ b/test/ExternalSCERC721Ledger.ts
@@ -15,9 +15,9 @@ import { expect } from 'chai'
 import { splitSignature } from 'ethers/lib/utils'
 
 const mintFunctionSignature =
-  'mint((uint256[2],uint256[2][2],uint256[2],uint256[46]),bytes,bytes32,bytes32)'
+  'mint((uint256[2],uint256[2][2],uint256[2],uint256[6]),bytes,bytes32,bytes32)'
 const mintFunctionSignatureWithOnlyProof =
-  'mint((uint256[2],uint256[2][2],uint256[2],uint256[46]))'
+  'mint((uint256[2],uint256[2][2],uint256[2],uint256[6]))'
 
 const invalidEcdsaWallet = new ethers.Wallet(
   '0x3931dc49c2615b436ed233b5f1bcba76cdc352f0318f8886d23f3e524e96a1be'
diff --git a/test/SCERC721Ledger.ts b/test/SCERC721Ledger.ts
index f506062..1beedb6 100644
--- a/test/SCERC721Ledger.ts
+++ b/test/SCERC721Ledger.ts
@@ -221,11 +221,7 @@ describe('SCERC721Ledger and SCERC721Derivative contracts tests', () => {
       await expect(
         this.scERC721Ledger.mint({
           ...balanceInput,
-          input: [
-            ...balanceInput.input.slice(0, -2),
-            invalidAttestorPublicKey,
-            balanceInput.input[balanceInput.input.length - 1],
-          ],
+          input: [...balanceInput.input.slice(0, 5), invalidAttestorPublicKey],
         })
       ).to.be.revertedWith('This ZK proof is not from the correct attestor')
     })
diff --git a/test/SCFarcasterLedger.ts b/test/SCFarcasterLedger.ts
index f543923..320fb1c 100644
--- a/test/SCFarcasterLedger.ts
+++ b/test/SCFarcasterLedger.ts
@@ -188,7 +188,7 @@ describe('SCFarcasterLedger and SCFarcasterDerivative contracts tests', () => {
     })
     it('should not mint if the attestor is incorrect', async function () {
       const farcasterInput = getFakeFarcasterProof(123)
-      farcasterInput.input[10] = invalidAttestorPublicKey
+      farcasterInput.input[11] = invalidAttestorPublicKey
       await expect(
         this.scFarcasterLedger.mint(farcasterInput)
       ).to.be.revertedWith('This ZK proof is not from the correct attestor')
@@ -196,11 +196,19 @@ describe('SCFarcasterLedger and SCFarcasterDerivative contracts tests', () => {
     it('should not mint if the "farcaster" word is incorrect', async function () {
       const farcasterInput = getFakeFarcasterProof(123)
       // Corrupt the message
-      farcasterInput.input[0] = 0
+      farcasterInput.input[1] = 0
       await expect(
         this.scFarcasterDerivative.mint(farcasterInput)
       ).to.be.revertedWith('This ZK proof is not from the farcaster')
     })
+    it('should not mint if attestation type is invalid', async function () {
+      const farcasterInput = getFakeFarcasterProof(123)
+      // Corrupt the message
+      farcasterInput.input[0] = 1
+      await expect(
+        this.scFarcasterDerivative.mint(farcasterInput)
+      ).to.be.revertedWith('Invalid attestation type')
+    })
     it('should not mint if nullifier has already been used', async function () {
       await this.scFarcasterDerivative.mint(getFakeFarcasterProof(123))
       await expect(
diff --git a/test/utils.ts b/test/utils.ts
index f90b7f1..273b98c 100644
--- a/test/utils.ts
+++ b/test/utils.ts
@@ -49,9 +49,9 @@ export async function getFakeBalanceVerifier(signer: SignerWithAddress) {
           type: 'uint256[2]',
         },
         {
-          internalType: 'uint256[46]',
+          internalType: 'uint256[6]',
           name: 'input',
-          type: 'uint256[46]',
+          type: 'uint256[6]',
         },
       ],
       name: 'verifyProof',
@@ -130,7 +130,7 @@ export async function getFakeFarcasterVerifier(signer: SignerWithAddress) {
         {
           internalType: 'uint256[11]',
           name: 'input',
-          type: 'uint256[11]',
+          type: 'uint256[12]',
         },
       ],
       name: 'verifyProof',
@@ -227,19 +227,22 @@ function getFakeBalanceVerifierInput(
   contract: string,
   network: Network,
   nullifier: number,
-  threshold: number
+  threshold: number,
+  type = 0
 ) {
   return [
-    ...ethers.utils.toUtf8Bytes(contract.toLowerCase()),
+    type,
+    BigNumber.from(contract.toLowerCase()),
     network,
+    threshold,
     nullifier,
     attestorPublicKey,
-    threshold,
   ]
 }
 
-function getFakeFarcasterVerifierInput(nullifier: number) {
+function getFakeFarcasterVerifierInput(nullifier: number, type = 0) {
   return [
+    type,
     ...ethers.utils.toUtf8Bytes('farcaster'),
     nullifier,
     attestorPublicKey,