Specification: Item Name: Insulation Plate for Flight Controller or ESC Version: 20x20mm Or 30.5x30.5mm ( Optional) Quantity: 1 PC The Thickness of Plate: 1mm 20x20mm Version is compatible for ESC / FC with 20x20mm Mounting Hole 30.5x30.5mm Version is compatible for ESC / FC with 20x20mm /30.5x30.5mm Mounting Hole Function: Short Circuit Protection