<div class="btn-group">

  <button type="button" class="btn btn-primary">Test</button>

  <button type="button" class="btn btn-primary dropdown-toggle" data-toggle="dropdown">

    <span class="sr-only"></span>

  </button>

  <ul class="dropdown-menu" role="menu">



<li><a href="link1.php">Link 1</a></li>



<li><a href="link2.php">Link 2</a></li>

</ul></div>