Orca Men's Apparel Size Chart The Orca Core Tri Tank, popular with triathletes of all levels, is constructed from three performance fabrics - AquaGlide, Tri-Mesh and Vapour - for speed through the water and performance, comfort and breathability on land. Its lightweight construction is quick drying and has low drag in the water. Vapour side panels and a mesh back give it excellent breathability and cooling. Features: - All new lighter weight AquaStretch fabric dries faster and provides improved breathability, while the Orca Enduro Water repellent coating improves glide through the swim - Next generation Vapour side panels provide extra breathability and comfort and a Soft Mesh back panel provides even more breathability where you need it most. - Two angled rear covered pockets positioned on either side of the lower back give you plenty of room to store the nutrition you need within easy reach in a place that won't bounce around - Reflective print ensures you stay visible when the light starts to drop