YAMAMOTO Neoprene all through. This super stretch panel is also velcro proof, so doesn't snag. Taping on stress point areas on all suits. Mega-stretch neoprene on underarm & crotch panels. Solid metal PK zippers with spring pulls. Extra length on the cuff and leg length for extra comfort. Wrap around panels on the forearm for comfort and seal. Stretch panel at base of spine for comfort and fit. Rear pull-down zip on jacket & vest models.