Löyly-IKI, the largest IKI stove, holds 400 kg of stones for a superior sauna experience in large saunas (20–40 m³). Its massive stone capacity ensures long-lasting heat, even if the fire dims. The 1 m² furnace-to-stone contact area and heavy-duty spiral fire pipe enable rapid heating in about 1 hour, meeting the demands of avid sauna enthusiasts.