This chromatography column is made from high quality Borosilicate glass with a 'Rotaflo' stopcock and porosity 'O' Sinter as standard with a simple drip-feed outlet. The interchangeable PTFE key requires no lubrication. The column is easily cleaned and requires little or no maintenance.Socket Size: 14/23Length: 300mmStopcock Bore: 3mmOutlet Diameter: 10mmOverall Diameter: 20mm