˙KG-33 made of borosilicate glass
˙The tube wall is thick and uniform in thickness
˙Good heat transfer and corrosion resistance
˙13mm test tube with 13-415 screw cap
˙16mm test tube with 15-415 screw cap
˙20mm test tube with 18-415 screw cap
˙25mm test tube with 24-410 screw cap
˙38mm test tube with 38-430 screw cap