Transport and Universal Tubes wth Screw Caps. Globe Scientific. Transport Tubes Tube is polypropylene (PP) - Screw cap is Polyethylene (PE) Tube is self-standing with conical bottom Molded graduations Clear: 1224L57-L58 Amber: 1224L59 Dimensions: 16mm x 56mm (1224L57) Dimensions: 16mm x 92mm (1224L58-L59) Universal Tubes .