<div class="row">

    {% for i in 1..13 %}
    <div class="col-xs-6 col-sm-6 col-md-4">
        <div class="form-group text-center">
            <label class="switch" for="checkbox_{{ i }}">
                <input type="checkbox" id="checkbox_{{ i }}" />
                <div class="slider round"></div>
            </label>
            <p>caracteristica {{ i }}</p>
        </div>
    </div>
    {% endfor %}

</div>