3 available in different colors and all can interlock with each other as shown. Crafted from durable polypropylene, this Four Sided Modular Test Tube Rack is designed to organize your laboratory tubes with efficiency. Its multiple colors allow for easy distinction between different sample sets, and the rest-on-table design ensures a secure and stable hold. The rack's dimensions, approximately 7x3x2 inches make it a perfect fit for various laboratory settings, including biological, medical, and microbiological environments. Equipped to hold multiple test tubes from small eppendorf style to 50 ml conical tubes.