S ec t i o n 1 0 -P a g e8 May 2013 Roof Channel Description • 2 material grades - A36 and 65000psi minimum yield • Length and hole spacing - to customer specif cations • Width - nominal 5-1/2 inches • Thickness T -2 - minimum 0.100 inc T -3 - minimum 0.125 inch T -4 - minimum 0.145 inch T -5 - minimum 0.165 inch Design Featur es a) holes punched on the sides for hanging cables and ventilation materials b) channel ends have the cor ners r ounded - such r educing sharp cor ners and pr event cuts to the miners hands and backs in low coal www .dsiundergr ound.com