Heavy-duty springs engineered for subflooring installations in martial arts studios and gymnastics facilities. These 4-inch tall springs provide essential shock absorption and impact protection during high-intensity training and dynamic movements. Complete hardware package included — no additional fasteners or components needed. Simply install and secure to your subflooring system for immediate performance benefits. Designed to reduce stress on joints and equipment while extending the lifespan of your training surface. Ideal for dojos, gyms, and training spaces where durability and safety are non-negotiable.