Type DSH double leaf smoke vents are the most economical way to add fire venting protect in large areas such as warehouses or manufacturing facilities. Frame opening: 48" x 48".Aluminum cover& galvanized steel curb

Type DSH double leaf smoke vents are the most economical way to add fire venting protect in large areas such as warehouses or manufacturing facilities. Frame opening: 48"W x 48"L. Aluminum Covers and Curb.

Type DSH double leaf smoke vents are the most economical way to add fire venting protect in large areas such as warehouses or manufacturing facilities. Frame opening: 48" x 72".Aluminum cover &galvanized steel curb

Type DSH double leaf smoke vents are the most economical way to add fire venting protect in large areas such as warehouses or manufacturing facilities. Frame opening: 48"W x 72"L. Aluminum Covers and Curb.

Type DSH double leaf smoke vents are the most economical way to add fire venting protect in large areas such as warehouses or manufacturing facilities. Frame opening: 48" x 90". Aluminum cover&galvanized steel curb

Type DSH double leaf smoke vents are the most economical way to add fire venting protect in large areas such as warehouses or manufacturing facilities. Frame opening: 48"W x 90"L. Aluminum Covers and Curb.

Type DSH double leaf smoke vents are the most economical way to add fire venting protect in large areas such as warehouses or manufacturing facilities. Frame opening: 48" x 96". Aluminum cover&galvanized steel curb

Type DSH double leaf smoke vents are the most economical way to add fire venting protect in large areas such as warehouses or manufacturing facilities. Frame opening: 48"W x 96"L. Aluminum Covers and Curb.