1、Designed for 16mm Tubes: These test tube racks are designed for 16mm / 0.6in test tubes or centrifuge tubes. 2、60 Holes: Each centrifuge tube holder is designed with 60 holes, ideal for home, school and laboratory use, meeting your needs. 3、3 Tiers: These test tube holders feature 3 tiers design, and they can be easily assembled or detached, saving your time and effort. 4、Wide Application: These centrifuge tube racks are great for test tubes holding beads for jewelry making, holding gumballs, treats, for gift, holding liquids for experiment. 5、Strong Plastic: These 16mm test tube racks are made of strong and durable plastic material, lightweight and detachable, easy to clean and carry. Item Type: Test Tube Rack Material: Plastic Application: Designed For 16mm / 0.6in Test Tubes, 60 Holes For Each Rack Product Size: Approx. 24.6 x 11.9 x 6.8cm / 9.7 x 4.7 x 2.7in (Manual Measurement, Slight Error May Exist) 1 x White Test Tube Rack Baseplate 2 x White Test Tube Rack Main Plate 1 x Blue Test Tube Rack Baseplate 2 x Blue Test Tube Rack Main Plate 1 x Yellow Test Tube Rack Baseplate 2 x Yellow Test Tube Rack Main Plate 3 x User Manual