Performance Technologies: Patented S3 Shock Suspension System 2 sets of stainless steel double springs Designed to withstand & absorb 80+ MPH frontal impacts from softballs Additional Details: Cage construction: protective powder-coated finish on hybrid hollow and stolid steel Adjustable padding system Elastic harness with ponytail opening Lightweight Patents 9,949,523 and 10,912,345 (independently tested) For softball use only