Air Mixing Technology- Saunum's patented air blending system mixes cold, oxygen-rich air from the floor with hot, oxygen-poor air from the ceiling. This solves the discomfort often associated with saunas, delivering heat and oxygen evenly from head to toe-whether you prefer it extremely hot or just warm. European Design- Features an elegant black steel finish that blends Scandinavian design with high-quality materials. Massive Stone Capacity- Stones are the heart of a Nordic sauna. Greater stone capacity results in softer, more even heat, and can produce more luxurious steam. The Air L boasts a massive 198 pound stone capacity. Himalayan Salt Reservoir- Himalayan Salt Spheres are positioned in the air stream to release beneficial salt ions throughout the sauna for added health benefits. Suitable for sauna rooms from459 to 741 cu. ft.