The Astrospec OTG 3001 offers an economical alternative to custom prescription eyewear programs. Features 4-way adjustable temple lengths for a custom fit. Duoflex temples are cushioned to relieve behind the ear pressure. Browguard and side shields for complete eye protection. Polycarbonate lenses are easy to replace. Some styles available with 3.0 and 5.0 welding shade lenses. Meets ANSI Z87.1 and CSA Z94.3 standards. Also available are OTG Bumpers, once applied they prevent your vision glasses or PC vision glasses from connecting with the OTG glasses. *Impact resistant nylon frames. *Single, replaceable polycarbonate lens with molded side shields. *Ultradura or uvextreme lens coating. *Seven contemporary frame colors. *Designed to fit over prescription eyewear. *Impact resistant and lightweight. *Available with soft cushion duoflex temples for extra added comfort. *Made in the USA.