Not sure why I'm so interested in this topic since I'm not in the market for a knife, but I like knives.
If I wanted a fixed blade PFD dive knife with a click sheath, I'd think seriously about the Benchmade 110H20, a video review of which I've linked below.
It's high quality corrosion resistant N680 stainless steel with a 3.43" blade and a grippy Santoprene handle. It is plain edge to hold the sharpest possible edge, or it also comes in a combo edge. It has a prying/digging tip and and a strap/rope cutting notch, and it only weighs 3.1 oz. Benchmade also has a lifetime sharpening service (only for plain edge knives) where you only pay for the shipping back and forth to them.
This knife should give multi-use service as a PFD "rescue" knife, a camp knife and a kitchen knife.
Shop around and you can probably find it heavily discounted. Or you can register on the Benchmade site as a serviceman, peace officer or law official and get it from the manufacturer for $73.50.
The combo edge is not shown on the video, but you can see it on the Benchmade site. BM probably won't sharpen the serrated half under its Lifesharp service. Ask.
The Kayak Wing
Paddler's Truck Rack
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