Kefir Set - The Benefits of Kefir. Contains probiotics and helps restore the natural balance of bacteria in the gut. It may be suitable for people with lactose intolerance, as the lactic acid in kefir breaks down the lactose in milk. Packed with nutrients, it contains vitamins A, D, K, B vitamins, and calcium. This set has been specifically designed for easy preparation and serving of kefir. It includes a 500 ml wide-mouth jar, a silicone lid, a stainless steel lid, and a measuring/mixing spoon. Measurement indicators on the dosing side and two sieve widths for thinner or thicker mixtures are also included.