Men's LavaCore Hypoallergenic Wetsuit Jacket Lavacore's thermal and neutral buoyancy properties are ideal under a wetsuit for added insulation or as a stand alone exposure protective garment. The unique make-up of materials eliminates constriction and allows extreme movement and flexibility, protecting and enhancing your inner core. The soft internal fleece combined with high 4-way stretch material produces the ultimate comfort / warmth / weight ratio. The Lavacore products are also excellent wetsuit alternatives to those with neoprene allergies, as the line does not contain neoprene and does not undergo vulcanization.