if you buy some make sure they are sealed.  after installing mine and drilling a hole on top of the gunwale for the foam I found that by compressing the cavity behind the holds with my lungs that they leaked air.  so I pulled the turf and foam off, applied some resin and returfed.....and you dont ever want to have to turf those things.  :grumble:  but they do look cool and hold you very well.