Plastic Test Tube Rack for 15/18 mm Tubes - Holds 50, Detachable

In this review the Plastic Test Tube Rack for 15/18 mm tubes is judged as a practical, low-cost organizer for small cylindrical vials and craft containers; its single biggest reason to buy is the compact, 50-place capacity that keeps tubes upright and accessible. The reviewer finds it well suited to hobby chemists, crafters making lip balm or chapstick, and anyone storing ink samples, and notes the rack's clear, laboratory-grade polystyrene construction and three-layer hole design as decisive features in everyday use.

Key Features

• 50-Place Capacity: Holds up to fifty tubes so users can sort samples, batches, or colors without crowding a workbench.
• Fits 15 to 18 mm Tubes: The 18.7 mm hole diameter accepts tubes with outer diameters from 15 mm to 18 mm, covering common small vials and chapstick containers.
• Three-Layer Support: A stacked, three-layer design with smaller holes at the bottom keeps tubes steady and prevents tipping during handling.
• Detachable Shelves: Slides together from one side with a stopping lip on the other, enabling compact storage and easier cleaning or transport.
• Laboratory-Grade Polystyrene: Lightweight but reasonably durable for routine organizing and display, while remaining clear for quick visual identification of contents.

Who It's For

This rack is best for makers and small labs that work with narrow tubes: fountain pen ink collectors, DIY lip balm creators, essential oil testers, and crafters who need a tidy, upright way to stage small cylinders. The clear finish and 50-place layout make it easy to catalog colors and batches at a glance.

Those needing an autoclavable or heavy-duty metal rack should look elsewhere, and anyone with tubes substantially larger than 18 mm OD will need a different size. If you require a rack with fixed, non-detachable construction for maximum ruggedness, this lightweight polystyrene option may not be ideal.

Pros & Cons

Pros

• High storage capacity that organizes up to fifty small tubes efficiently.
• Clear polystyrene lets users see tube labels and colors without removing samples.
• Three-layer hole arrangement improves stability and prevents tubes from wobbling.
• Detachable design makes it easier to disassemble for transport or compact storage.

Cons

• Not autoclavable, so it is unsuitable for workflows that require steam sterilization.
• Some users may find the snap-together assembly fiddly compared with single-piece racks.

Specifications

Brand	Karter Scientific
Capacity	50 holes
Hole diameter	18.7 mm (0.74 in)
Tube OD compatibility	15 mm to 18 mm
Material	Laboratory-grade polystyrene (clear)
Design	Detachable, three-layer with stop lip

Our Verdict

The Plastic Test Tube Rack for 15/18 mm tubes is a sensible, budget-friendly organizer for hobbyists and small labs who need to store many narrow tubes in a compact footprint. It is particularly good value for those collecting ink samples, making lip balm, or staging essential oil vials, offering clear visibility and reasonable stability, but it is not suited to high-heat sterilization or heavy industrial use.

Frequently Asked Questions

Will it fit a chapstick tube?
Yes; the rack accepts tubes with an outer diameter between 15 mm and 18 mm, which covers most standard chapstick and small lip balm containers.

Is the rack autoclavable?
No; the laboratory-grade polystyrene used is not autoclavable and should not be subjected to steam sterilization.

Is assembly difficult?
Assembly is slide-together with a stopping lip; many users find it straightforward, though some report it requires careful alignment to fit snugly.