Babcock Davis BRHRA Retrofit Roof Hatch in Aluminum is a replacement roof hatch. Easy installation, attaches to existing curbs. 11 gauge Aluminuim. Mill Finish. Low profile 4-inch curb and safety railing ready. The Babcock-Davis BRHRA Aluminum Retrofit Roof Hatch works with existing roofing systems and attaches quickly and easily to existing curbs. Save time and labor costs with this easily installed...