function wbids_savings_custom(id, value, price)
{
    var negaback_el = document.getElementById('item_'+id+'_negaback');
    var savings_el = document.getElementById('item_'+id+'_savings');

    var negaback = Math.floor((((price > 100 ? 100 : price) - 0.01) / 10) + 1) * 10;
    negaback_el.innerHTML = negaback + ' €';
    savings_el.innerHTML = formatPrice(negaback + value);
}