I found some old fins today and thought I'll try them on the 8'11 Blurr V2. The centre fin is 6 inches and the sides are a little over 4.5 inches.
I moved the centre fin forward which made the board slightly looser, but these fins gave the board more, drive and easier to turn.
Don't know why but it worked. Happy days.

I have been trying Mike's February Twin fins with a small Quobba as a trailer fin. goes really well together.

Does it feel real loose Antho?

Hey Steveo
The board is definitely looser and feels faster.

Should be Mikey February Twin Fins

I'll give it a go.