Regarding the above matter, we have made the following changes in our Oak Ridge Super catalog and manual: 1. The minimum slope was previously set at 2.5 shaku, but we have now allowed for installation with a slope of 2 shaku or more, regardless of whether it is in general or heavy snowfall areas. (Revised in April 2019) 2. We have expanded the maximum flow length uniformly to 30 meters or less, regardless of whether it is in general or heavy snowfall areas. (Revised in May 2019) We appreciate your continued support of our products.