<form target="paypal" action="https://www.paypal.com/cgi-bin/webscr" method="post">
<input type="hidden" name="cmd" value="_s-xclick">
<input type="hidden" name="hosted_button_id" value="Z7KZKM2XU77XG">
<table>
<tr><td><input type="hidden" name="on0" value="Conditionnement">Conditionnement</td></tr><tr><td><select name="os0">
    <option value="500g">500g €9,95</option>
    <option value="4 Kg">4 Kg €39,95</option>
</select> </td></tr>
</table>
<input type="hidden" name="currency_code" value="EUR">
<input type="image" src="http://www.futurelabmuscle.com/templates/caprica/images/btn_commandez.jpg" border="0" name="submit" alt="PayPal - la solution de paiement en ligne la plus simple et la plus sécurisée !">
<img alt="" border="0" src="http://www.futurelabmuscle.com/templates/caprica/images/btn_commandez.jpg" width="1" height="1">
</form>