5" Flat Side Extension Plates are used to extend the mounting hole locations. It is recommended for use with the Offset Mounting Brackets.
The kit consists of 2 brackets. The brackets are available in Obsidian Black (J0016-OB) and Pearl White (J0016-OB), to match your STD2 air curtain. And available in Titanium Silver (J0016-TS) for your HV2 air curtain.