var promoSlider = $('.promo-slider'),
    promoSliderCurrentIndex = $('.product-card__main-list-counter-current'),
    promoSliderAllIndex = $('.product-card__main-list-counter-all');

promoSlider.owlCarousel({
  loop: false,
  items: 1,
  margin: 0,
  nav: true,
  dots: false,
  onInitialized: function(e) {
    promoSliderAllIndex.text(e.item.count / e.page.size);
  },
  smartSpeed: 1000
});

promoSlider.on('changed.owl.carousel', function(e) {
  promoSliderCurrentIndex.text(Math.ceil(e.relatedTarget.current() + 1));
});