Liquid & Gas Level Indicator Strips – Adhesive‑Backed Thermochromic Strips

These adhesive‑backed thermochromic strips provide a fast, clear visual indication of the level of liquids or gases inside a wide range of containers. Simply apply the strip to the outside surface and watch the colour change reveal the fill line.

How it works

When liquid or liquefied gas is present behind the container wall, it absorbs heat differently to the vapour above it. By applying gentle heat to the outside of the container, the thermochromic strip reacts to this temperature difference and displays a visible colour change exactly at the level of the contents.

Why customers choose these strips

• Works with both liquids and gases – ideal for tanks, cylinders, drums and vessels
• Adhesive‑backed – simple to apply to most clean, dry surfaces
• Fast response – clear colour change within seconds once heat is applied
• No batteries or electronics
• Lightweight and low‑cost – suitable for industrial, laboratory and home use

Why this one is better

• Made using high‑quality thermochromic materials for a sharper colour transition
• Reliable performance across a wide temperature range
• Strong, durable adhesive backing
• More versatile than magnetic LC indicators – suitable for liquid containers as well as gas bottles

Works with these container types

• Steel and aluminium gas cylinders
• LPG, Butane and Propane bottles
• Water tanks and reservoirs
• Chemical drums
• Fuel containers
• General liquid storage vessels

How to use

1. Ensure the container surface is clean and dry.
2. Peel off the backing and apply the strip vertically, ensuring full contact with the surface.
3. Apply heat using a hairdryer on a warm setting, or by pouring hot (not boiling) water over the outside of the container.
4. Move the heat source back and forth across the strip for a few seconds until the colour changes.
5. The strip will turn from black to orange. Once the heat is removed, the area above the liquid level will return to black. The point where orange meets black indicates the approximate level.

Dimensions

Standard size: 200 × 20 mm

Important notes

• This product indicates level, not gas leaks.
• Designed to work best between 14°C and 40°C. Outside this range, the colour change may be slower or less pronounced.
• Provides an approximate indication only. Container shape, ambient temperature and contents may affect accuracy.
• Adhesive strips may be repositioned if handled carefully, but are not classed as fully reusable.