Brooks Lady Defyance 4 Running Shoes HPR Plus Outsole - a highly durable rubber compound to reduce wear and increase the life o BIOMOGO - Brooks introduces the first-ever biodegradable running shoe midsole. DRB - ACCEL - This system helps to promote natural movement between the heel and forefoot. Rear and Forefoot Hydroflow Cushioning - the contained silicone-oil compound dampens the i Weight: 249g