For installation of the rail side fin on a thruster fin set up. These fin plugs are super handy as they are totally transparent. his means you can see the colour or your pigmented mix through the plug. So if you want a green plug use green pigment.... blue plug use blue pigment etc. Exactly the same size as FCS branded FCS I plugs. 

Great priced plug for repair or making your own board.

Note: Price is per plug, you will need two centre plugs and four rail plugs for a standard thruster set up