2 packs 25mm wide 90 degree made of 4mm thick quartz with glow ball,14mm male (2) ciang reliable quality:100%made of quartz,high heat resistance<br> high temperature resistance?quartz glass can be used at 1100 ° c for a long time<br> good thermal stability. quartz glass has a very small coefficient of thermal expansion<br> can withstand severe temperature changes, and is stable at high temperatures<br> preservative. in addition to hydrofluoric acid, quartz glass hardly reacts with other acids<br> <br> premium quality, price match guarantee, please rest assured to buy<br> please feel free to contact our customer support team when you have any question,and you will receive a satisfactory reply