While I have yet to put my Surf Knobs through their paces in the Ocean (surfing), I did install them on my Wavestorm and paddled around on a nearby lake ... only to have an adhesive failure with one. Rob, at Surf Knobs, promptly sent me replacement adhesive. I’ll give them another trial at the lake before trusting them as a functional “assistive device” in my unashamed quest to learn to surf “before I die”. (I’m 71 years old ... so it’s a “race”).