The Siren Sport Leather from Merrell has a higher degree of durability afforded by a pigskin leather upper. Synthetic leather strapping provides lateral and medial support while anchoring-with narrow gauge webbing-the easy -to-snug lacing system. Topped by a midsole with Merrell Air Cushion and Q-form stride alignment. The two-color Vibram Siren sole reveals braking gripping and water-siphoning zones.