McNICHOLS® Stair Treads Bar Grating, Swage-Locked, Stair Tread, Rectangular Bar, GAL-150, 19-S-4 Spacing, Aluminum, Alloy 6063-T6, 1-1/2" x 3/16" Rectangular Bars, Smooth Surface, Corrugated 90° Angle Nosing, CP-BG-1230 Bar Grating Stair Tread Carrier Plates Attached, 77% Open Area