SPECIAL ORDER ITEM. Review Returns Policy before purchase. The Hart & Cooley storm collar provides a reliable seal for your venting system. Designed for 3 in applications, this component is constructed from durable galvanized steel meeting G90 material standards. With precise dimensions of 1-7/16 in H x 3-1/2 in ID x 6-5/8 in OD and a thickness of 0.018 in, it ensures a secure fit and long-lasting performance in various environmental conditions.