“Glass” or Fiberglass has been used in some graphite offerings in the past, but those shafts were usually cheaper “commercial” grade and are used more in cheap box sets, etc. We do not carry any shafts with fiberglass. I really don’t know if even box set shafts are still using 60/40 or 80/20 carbon fiber to glass shafts anymore. They used to because by using some glass the shafts cost less. You can get decent 100% graphite shafts now at reasonable prices so I am not sure if using glass is necessary to reduce the cost on the commercial grade product. I will reach out to some of my manufacturing friends and find out if glass, or fiberglass, is still used.