Android : How can I report the descripction in paypal from aplication android?

I am doing an application in android. I use PayPalPayment.class to connect with paypal, I want to report descripcion of her sold for it appear in more details.

Part of my code:

PayPalPayment thingToBuy = new PayPalPayment(new BigDecimal("4.99"), "EUR", "Datos de contacto - "+pro.getTitulo());

            Intent intent = new Intent(InfoProyecto.this, PaymentActivity.class);


            intent.putExtra(PaymentActivity.EXTRA_PAYPAL_ENVIRONMENT, CONFIG_ENVIRONMENT);
            intent.putExtra(PaymentActivity.EXTRA_CLIENT_ID, CONFIG_CLIENT_ID);
            intent.putExtra(PaymentActivity.EXTRA_RECEIVER_EMAIL, CONFIG_RECEIVER_EMAIL);
            // It's important to repeat the clientId here so that the SDK has it if Android restarts your 
            // app midway through the payment UI flow.
            intent.putExtra(PaymentActivity.EXTRA_CLIENT_ID, "APP-80W284485P519543T");
            intent.putExtra(PaymentActivity.EXTRA_PAYER_ID, "your-customer-id-in-your-system");
            intent.putExtra(PaymentActivity.EXTRA_PAYMENT, thingToBuy);


            startActivityForResult(intent, 0);