Nalgene* Unwire* Test Tube Retainers, Polyketone

Snap onto Unwire* test racks and securely hold tubes with individual, molded-in finger tabs. Fit 13 or 16 mm Unwire test tube racks. Hold tubes in rack in water bath or when rack is inverted to empty tube contents. Prevent tube movement on orbital mixers and shakers. Numbers and letters molded into upper surface for positive tube identification. Autoclavable.