It is a enclosed cabnet, but it's open with a large vent on the side to my tractor barn. I've used it for my two lyman 600's for about 5 years. They are getting worn and the small size is just too time consuming when I have a lot to do. I also insulate the cabnet on thew shop sides and the top. Very little noise at all with both tumblers running. barn is allways cool especially during any Michigan winter. Thanks for the help.