All our murrine are made of Murano glass (coefficient 104) and can be used with glass sheet, rods and grits of the same coefficient. Please note: The dimensions are variable. Durante description you will find the minimum and maximum diameter that you will find Sopra the package. Con the site https://bicchieri49371.weblogco.com/26723190/ottenere-il-mio-soffiato-to-work