1,Flat bottom ground flask(chemistry flask) 2,High temperature resistance and corrosion resistance 3excellent optical ... 3.3 borosilicate glass , heavy wall.3:Size: capacity(ML):5,, 10,, 25,, 50,,1 00,,150, ,250,, 500,, 1000,, 2000,, 3000 ... 45/50,,50/42,,55/50 4:Scope of application:for scientific research, teaching, medicine, and petroleum chemical industries. glass flat bottom flask(chemistry flask)