Specification: Item Name: Insulation Plate for Flight Controller or ESC Version: 16x16mm 20x20mm or 30.5x30.5mm The Thickness of Plate: 0.8mm (16x16mm), 1mm (20x20mm or 30.5x30.5mm) 16x16mm version is compatible for ESC / FC with 16x16mm Mounting Hole 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