Differences between K plane 280 vs 300
 

I was talking with Rob (RWS) last weekend and he was showing me the trim tabs on his Vector Python and mentioned he had K plane 300's on it and then switched them out for the 280's. I have see a lot of twin engine boats that have the 280's Were the 300's used mainly on single engine boats? The reason I ask is because my 38 Scarab has the 300's on it.

I may be wrong, but the 300 has a square tab where the 280 has a tapered tab, I believe the taper is just for clearance to the outdrive while turning. Single engine boats have more room so they don't need the taper. If the 300s clear on your Scarab, then there should be no problem.

My guess would be that the 300's were too wide and may have had clearance issues on many twin set ups.
I think the 280 is just a 300 with the inner side angle cut.