3.175 x 25.400 mm oblong slot
6.350 mm centers
Side Staggered
43% open
22 gauge steel
Length of oblong slots run length of sheet.
1/4" Slotted Perforated Metal:
6.350 x 38.100 mm slot
Every third bridge 4.763 mm wide
Other bridges 2.381 mm
67% open area of sheets
16, 18, 20 gauge steel
Length of slots runs width of perforated sheet.