diff --git a/package.json b/package.json
index 094c9be..145614b 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "bybit-api",
-  "version": "3.3.5",
+  "version": "3.3.6",
   "description": "Complete & robust node.js SDK for Bybit's REST APIs and WebSockets, with TypeScript & integration tests.",
   "main": "lib/index.js",
   "types": "lib/index.d.ts",
diff --git a/src/contract-client.ts b/src/contract-client.ts
index 465b6c6..eb227d3 100644
--- a/src/contract-client.ts
+++ b/src/contract-client.ts
@@ -23,6 +23,7 @@ import {
   ContractWalletFundRecordRequest,
   PaginatedResult,
   ContractHistoricOrder,
+  ContractSymbolTicker,
 } from './types';
 import { REST_CLIENT_TYPE_ENUM } from './util';
 import BaseRestClient from './util/BaseRestClient';
@@ -67,9 +68,9 @@ export class ContractClient extends BaseRestClient {
 
   /** Get a symbol price/statistics ticker */
   getSymbolTicker(
-    category: UMCategory,
+    category: UMCategory | '',
     symbol?: string
-  ): Promise<APIResponseV3<any>> {
+  ): Promise<APIResponseV3<ContractSymbolTicker[]>> {
     return this.get('/derivatives/v3/public/tickers', { category, symbol });
   }
 
diff --git a/src/types/response/contract.ts b/src/types/response/contract.ts
index 904af94..249e3d4 100644
--- a/src/types/response/contract.ts
+++ b/src/types/response/contract.ts
@@ -33,3 +33,27 @@ export interface ContractHistoricOrder {
   triggerDirection: number;
   positionIdx: number;
 }
+
+export interface ContractSymbolTicker {
+  symbol: string;
+  bidPrice: string;
+  askPrice: string;
+  lastPrice: string;
+  lastTickDirection: string;
+  prevPrice24h: string;
+  price24hPcnt: string;
+  highPrice24h: string;
+  lowPrice24h: string;
+  prevPrice1h: string;
+  markPrice: string;
+  indexPrice: string;
+  openInterest: string;
+  turnover24h: string;
+  volume24h: string;
+  fundingRate: string;
+  nextFundingTime: string;
+  predictedDeliveryPrice: string;
+  basisRate: string;
+  deliveryFeeRate: string;
+  deliveryTime: string;
+}
diff --git a/src/util/websocket-util.ts b/src/util/websocket-util.ts
index 520e7c0..c15d385 100644
--- a/src/util/websocket-util.ts
+++ b/src/util/websocket-util.ts
@@ -281,7 +281,7 @@ export function getWsKeyForTopic(
       }
 
       throw new Error(
-        `Failed to determine wskey for unified perps topic: "${topic}`
+        `Failed to determine wskey for unified perps topic: "${topic}"`
       );
     }
     case 'contractInverse': {