O'Neill Hammer 2/1 MM Wetsuit Jacket: Rider developed and rider proven, as with all O’Neill wetsuits, the O’Neill Hammer 2/1mm Wetsuit Jacket is the best of both worlds - added core body warmth and protection where you need it without the restriction of a full body suit. Waiting for that perfect wave is a long process but it’s made a little easier with the O’Neill Hammer 2/1mm Wetsuit Jacket.