I am very satisfied with the product. After I had to the plywood bulkhead to the anchor box a narrow ventilation slot due to ingress of water in bad weather (clogged drainage hole of the anchor box) had been formed by the only one-sided vent on the companionway a musty atmosphere in the cabin. This is eliminated after installation of the fan within a short time despite the current high heat and low wind. The ventilation effect is thus better than expected.