... , 47, 58, 70 for solar water heater. Usage:lighting, test tube Borosilicate glass tube 3.3 OD: 3mm~320mmColor: Clear / blue,green,yellow, purple ... , ground, rough Description:Material: high borosilciate glass 3.3Feature: heat-resistant, anti-acid, anti-alkaliApplication: Lab glass ware, solar vacuum tube, lighting, handcrafts