diff --git a/README.md b/README.md
index 9f75b93..7447b31 100644
--- a/README.md
+++ b/README.md
@@ -115,6 +115,8 @@ await msg91otp.retry("919999999999",true)
 
 **userip**        : `string` User IP
 
+**extra_param**   : Here you can pass the variables created in the SendOTP template.
+
 ### Licence: (MIT License)
 
 **Copyright (c) 2018 Sumeet Bhardwaj**
diff --git a/package.json b/package.json
index 5a8f093..e55db6c 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "msg91-lib",
-  "version": "2.0.1",
+  "version": "2.0.2",
   "description": "Unofficial msg91 library to send OTP & messages",
   "main": "index.js",
   "scripts": {
@@ -11,6 +11,7 @@
     "url": "git+https://github.com/sumitsk20/msg91-lib.git"
   },
   "homepage": "https://github.com/sumitsk20/msg91-lib/tree/v2.x",
+  "types": "./types/index.d.ts",
   "keywords": [
     "msg91",
     "otp",
diff --git a/src/msg91OTP.js b/src/msg91OTP.js
index 7c2addf..22568a0 100644
--- a/src/msg91OTP.js
+++ b/src/msg91OTP.js
@@ -55,7 +55,8 @@ class Msg91Otp {
         otp_expiry: args.expiry || this.defaultOtpExpiry,
         otp_length: args.otpLength || this.defaultOtpLength,
         email: args.email || '',
-        invisible: args.invisible || 1
+        invisible: args.invisible || 1,
+        extra_param: args.extra_param || ''
       }
     };
     return await makeRequest(options);
diff --git a/types/index.d.ts b/types/index.d.ts
new file mode 100644
index 0000000..55cf151
--- /dev/null
+++ b/types/index.d.ts
@@ -0,0 +1,29 @@
+interface IMsg91OtpConstructorArgs {
+  authKey: string;
+  templateId: string;
+  baseUrl?: string;
+  apiVersion?: string;
+  otpExpiry?: number;
+  otpLength?: number;
+}
+
+interface IMsg91SendOtpArgs {
+  templateId?: string;
+  expiry?: number;
+  otpLength?: number;
+  email?: string;
+  invisible?: 0 | 1;
+  extra_param: any;
+}
+
+declare class Msg91Otp {
+  constructor(args: IMsg91OtpConstructorArgs);
+
+  send(contactNumber: string | number, args?: IMsg91SendOtpArgs): Promise<any>;
+
+  retry(contactNumber: string | number, retryType?: string): Promise<any>;
+
+  verify(contactNumber: string | number, otp: number | string): Promise<any>;
+}
+
+export { Msg91Otp as msg91OTP };