AIR VENT FA109000 16.94x8 ALU Founda Vent FA109000 aluminum foundation vent with slider, mill, 36 sequin of net free area per piece, Rough opening is 16-15/16" x 8", replaces a 16" x 8" block in the foundation to allow air to flow across the foundation to help prevent heat moisture build up in the crawl space, vent is screened.This product adds a great value. Product is highly durable and very easy to use. This product is manufactured in china. Features This product adds a great value Product is highly durable and very easy to use This product is manufactured in China USA SHIPPING estimates delivery times and we work to get your item to you as quickly as possible and within those times, but please know it may take slightly longer than the estimate.