minishop2 корзина как сделать input в графе "вес" как и у "количество"?

<?php
switch ($modx->event->name) {
        case 'msOnChangeInCart':
            $modx->log(1, print_r($_POST,1,'HTML'));
            $tmp = $cart->get();
            $modx->log(1, print_r($tmp,1,'HTML')); 
            $tmp[$key]['price'] = $_POST['price2'];
            $cart->set($tmp);
         break;
}

<form method="post" class="ms2_form" role="form">
                                <input type="hidden" name="key" value="{$product.key}"/>
                                <div class="form-group">
                                    <div class="input-group input-group-sm">
                                        <input type="number" name="price2" value="" class="form-control"/>
                                        <div class="input-group-append">
                                            <span class="input-group-text">{'ms2_frontend_currency' | lexicon}</span>
                                        </div>
                                    </div>
                                    <button class="btn btn-sm" type="submit" name="ms2_action" value="cart/change">↻</button>
                                </div>
                            </form>