Replace wood blocking on roof sheathing. Tight fit for positive installation. Embossed dimples provide 1/8 in gap needed to prevent panels from popping up as sheathing expands. G60 galvanizing finish. 20 ga, Boxed.
Provide structural support
Reduce normal plywood deflection between panels
Embossed dimples/built-in spacer type feature provide APA recommended 1/8 in gap