<form method='POST' action='https://sandbox.google.com/checkout/api/checkout/v2/checkoutForm/Merchant/REPLACE_WITH_YOUR_SANDBOX_MERCHANT_ID' accept-charset='utf-8'>
<!-- Sell physical goods and services with possible tax and shipping -->
  <input type='hidden' name='item_name_1' value='5 lbs. Dog Food'/>
  <input type='hidden' name='item_description_1' value='5 lb. bag of dog food'/>
  <input type='hidden' name='item_price_1' value='35.00'/>
  <input type='hidden' name='item_currency_1' value='USD'/>
  <input type='hidden' name='item_quantity_1' value='1'/>
  <input type='hidden' name='item_merchant_id_1' value='5LBDOGCHOW'/>

<!-- No tax code -->

<!-- No shipping code -->

<input type='hidden' name='_charset_' />

  <!-- Button code -->
  <input type='image'
    name='Google Checkout'
    alt='Fast checkout through Google'
    src='http://sandbox.google.com/checkout/buttons/checkout.gif?merchant_id=REPLACE_WITH_YOUR_SANDBOX_MERCHANT_ID&w=180&h=46&style=white&variant=text&loc=en_US'
    height='46'
    width='180' />

</form>