Glass Culture Cylinder Starter Set (2, 4, 6, 8, 10 mm i.d x 5mm high) by AutoMate Scientific Inc.

Culturing Cylinders are used to barricade cells or suspended specimens in a Delta T® Culture Dish or to restrict and concentrate the growth and location of cells plated on an FCS2® Coverslip. They are 5mm high and available in a variety of inside diameters including 1mm, 2mm, 4mm, 6mm, 8mm, 10mm, and 12mm. The outer diameter is always 2mm greater than the inside diameter due to the 1mm wall thickness. The cylinders are made of Pyrex glass and are heavier than plastic cloning rings to eliminate floating. They are optically polished on the bottom surface to mate with and form a tight seal with other glass surfaces such as FCS2® Coverslips and Delta T® Culture Dishes without the need of grease. Culturing Cylinders can be autoclaved for reuse.
No grease, no contamination, reuseable!