diff --git a/src/utils/signature.ts b/src/utils/signature.ts
index d3b40c8..7258a1f 100644
--- a/src/utils/signature.ts
+++ b/src/utils/signature.ts
@@ -1,5 +1,6 @@
 import { Hash } from "viem";
 import { JSONRPCResponse } from "../types/rpc";
+import { MPCSignature } from "../types/types";
 
 export async function signatureFromTxHash(
   nodeUrl: string,
@@ -7,7 +8,7 @@ export async function signatureFromTxHash(
   /// This field doesn't appear to be necessary although (possibly for efficiency),
   /// the docs mention that it is "used to determine which shard to query for transaction".
   accountId: string = "non-empty"
-): Promise<[string, string]> {
+): Promise<MPCSignature> {
   const payload = {
     jsonrpc: "2.0",
     id: "dontcare",
@@ -31,7 +32,8 @@ export async function signatureFromTxHash(
   if (base64Sig) {
     // Decode from base64
     const decodedValue = Buffer.from(base64Sig, "base64").toString("utf-8");
-    return JSON.parse(decodedValue);
+    const [big_r, big_s] = JSON.parse(decodedValue);
+    return { big_r, big_s };
   } else {
     throw new Error("No valid values found in the array.");
   }
diff --git a/tests/unit/utils.signature.test.ts b/tests/unit/utils.signature.test.ts
index 525b36e..b78380b 100644
--- a/tests/unit/utils.signature.test.ts
+++ b/tests/unit/utils.signature.test.ts
@@ -8,10 +8,11 @@ describe("utility: get Signature", () => {
 
   it("successful: signatureFromTxHash", async () => {
     const sig = await signatureFromTxHash(url, successHash);
-    expect(sig).toEqual([
-      "03EA06CECA2B7D71F6F4DA729A681B4DE44C6402F5F5BB9FC88C6706959D4FEDD4",
-      "67986E234DEC5D51CF6AED452FE1C4544924218AC20B009F81BAAE53C02AFE76",
-    ]);
+    expect(sig).toEqual({
+      big_r:
+        "03EA06CECA2B7D71F6F4DA729A681B4DE44C6402F5F5BB9FC88C6706959D4FEDD4",
+      big_s: "67986E234DEC5D51CF6AED452FE1C4544924218AC20B009F81BAAE53C02AFE76",
+    });
   });
   it("failed: signatureFromTxHash", async () => {
     await expect(signatureFromTxHash(url, failedHash)).rejects.toThrow(