ForceFlex® technology incorporates a patented, multi-injection molding of the lens with a flexible Thermo Plastic Urethane (TPU) frame. Due to this construction, it can achieve a military ballistic level impact resistance at over 1000 feet per second. The TPU material allows the frame to flex and fit individual faces from large to small. All ForceFlex® safety glasses meet military MIL-PRF-31013 clause 188.8.131.52 for high velocity impact protection and exceed ANSI Z87+. This achievement benefits consumers by providing unparalleled levels of protection. The dual material temples combine Thermo Plastic Rubber (TPR) for comfort and polycarbonate for durability. MCR Safety's Professional Grade eyewear is engineered to provide the highest level of innovation for consumers that demand the very best in safety.