125mm S/S Mushroom dome vent
Mushroom style Stainless Steel Dome Vent with flat lid and internal grill to help stop flying night bugs. Base in nylon - Cut out hole size in deck : 120mm, maximum outside diameter 155mm. Maximum height when closed 37mm above deck, Maximum height when open generally 57mm. Not really designed to be walked on.
As air passes over the top of the vent with natural on deck air flow, this creates a vacuum and a wind pattern that allows air to be drawn up from below, thus the mushroom effect is best at getting air out rather than air into the boat. Often used on anchor locker lids, hatch lids and where warm air accumulates.