Bootstrap 3 input groups size

<!DOCTYPE html>
<title>My Example</title>

<link rel="stylesheet" href="//maxcdn.bootstrapcdn.com/bootstrap/3.3.5/css/bootstrap.min.css">
<div class="container-fluid">
		
<div class="input-group input-group-sm">
<span class="input-group-addon">
<span class="glyphicon glyphicon-phone-alt" aria-hidden="true">
</span>
</span>	
<input type="tel" class="form-control" aria-label="Phone Number" placeholder="Small">
</div>

</div>
		

<script src="//ajax.googleapis.com/ajax/libs/jquery/1.11.3/jquery.min.js"></script>

<script src="//maxcdn.bootstrapcdn.com/bootstrap/3.3.5/js/bootstrap.min.js"></script>

<script>
// Initialize tooltip component
$(function () {
  $('[data-toggle="tooltip"]').tooltip()
})

// Initialize popover component
$(function () {
  $('[data-toggle="popover"]').popover()
})
</script>