15' Extra Heavy-Duty Expedition Inflatable KaBoat SK470XL Extra thick 1.5mm PVC bottom, compare to standard 0.9mm PVC. Bottom of tubes overlapped with additional layer of PVC up to the rub strake protectors. New 2013 model SK470XL have shorter and lighter aluminum seats, triangular splash guards over transom corner, and grommet splash strip with rope all along boat tubes. Same heavy-duty 1100 Denier PVC as in SATURN boats & rafts. Front spray skirt with water deflector guard and rope lacing. Marine grade plywood transom with a one way drain plug. Extra thick, high-pressure 6" (140mm) inflatable air deck floor. Durable rub strake protectors along boat tubes. 4 fins on bottom of tubes for improved tracking. 4 (four!) separate air chambers for extra safety. 2 sets of rowing oars with 2 sets of oar locks for tandem rowing. 3 lightweight aluminum removable benches. Included: hand pump, repair kit, 4 oars and carry bag.