Dear my friend, Nice to meet you. This is Rose from Hengshui Aohong Technology Co.,Ltd. We are a professional factory of gauge glass & sight glass. Our products have been exported to many countries. The products are as follows: 1. Reflex gauge glass ( 3 lines 4 grooves ) & Transparent gauge glass 340 x 34(30) x 17mm 320 x 34(30) x 17mm 280 x 34(30) x 17mm 250 x 34(30) x 17mm 220 x 34(30) x 17mm 190 x 34(30) x 17mm 165 x 34(30) x 17mm 140 x 34(30) x 17mm 115 x 34(30) x 17mm 420 x 34 x 17mm 370 x 34 x 17mm 300 x 34 x 17mm and some other special size gauge glass can be customized according to your drawings. 2. Sight glass: round, Rectangular & square , tubular sight glass 3. Glass road stud,reflective glass road studs, reflective road studs. 4. Material: tempered soda lime glass, tempered borosilicate glass, tempered borosilicate 3.3, quartz. 5. Packing: paper box, carton , plywood case. or according to requirement. 6. Gasket: asbestos rubber gaskets ,non-asbestos rubber gaskets, graphite gasket,PTFE gasket,micashield . 7. Printing: we can print on the glass according to requirements. Any question, please feel free to tell me. I will do my best! Thanks&Best regards,