This SK ROTAMETER GLASS TUBE NO. S&K-3/4-31-G-10 /  SK 3/4-31-G-10 / METER SIZE 5 is in great condition and is guaranteed to be fully functional. These tubes came from a local lab that had surplus overstocked inventory. Tubes are most likely in unused condition but were listed as used due to lack of factory packaging. We urge customers to view all photos as they show overall condition, included accessories and useful information. Please feel free to contact us with any questions.