Fit for Fan Size: 40 x 40mm/ 1.57" x 1.57"(L*W) Fence Material: C1008 Shiny Metal Wire; Color: Silver Surface Treatment: Nickel plating, weld can withstand 88 pounds tensile testing. Installing Hole Spacing: 32.5 x 32.5mm/ 1.25" x 1.25"(L*W) Package Conetnt: 20 x Fan Metal Finger Grill / Guard