1: Chapters Last updated Save as PDF Page ID 5163 1.1: Chapter 1 Flat Pan 1.2: Rectangular Sleeve 1.3: Circumference and Bisecting Angles 1.4: 2 piece 90° 1.5: 3 Piece 90° 1.6: Branch and Header Connections 1.7: Concentric 90° Branch on Header 1.8: Eccentric Branch 1.9: 45 lateral branch