diff --git a/basics/account-data/poseidon/account-data-program/ts-programs/src/accountDataProgram.ts b/basics/account-data/poseidon/account-data-program/ts-programs/src/accountDataProgram.ts
index 163fd75d..49037acf 100644
--- a/basics/account-data/poseidon/account-data-program/ts-programs/src/accountDataProgram.ts
+++ b/basics/account-data/poseidon/account-data-program/ts-programs/src/accountDataProgram.ts
@@ -1,10 +1,10 @@
-import { Account, Pubkey, Result, Signer, u8, u16, u32 } from '@solanaturbine/poseidon';
+import { Account, Pubkey, Result, Signer, u8, u16, u32, String } from '@solanaturbine/poseidon';
 
 export default class AccountDataProgram {
   // Following Poseidon example pattern of static PROGRAM_ID
   static PROGRAM_ID = new Pubkey('JvF1QDhgab1ARhACPWTAZnUymthGGmn3NXCj8i6mjSQ');
 
-  create_address_info(payer: Signer, state: AddressInfo, name: string, houseNumber: u8, street: string, city: string): Result {
+  create_address_info(payer: Signer, state: AddressInfo, name: String<50>, houseNumber: u8, street: String<50>, city: String<50>): Result {
     // Use nit() for initialization
     state.derive(['address_info', payer.key]).init(payer);
     // Store the account data
@@ -16,8 +16,8 @@ export default class AccountDataProgram {
 }
 
 export interface AddressInfo extends Account {
-  name: string;
+  name: String<50>;
   houseNumber: u8;
-  street: string;
-  city: string;
+  street: String<50>;
+  city: String<50>;
 }