Plastic Shims & Gaskets
When you need expertise.
PSG were the original inventors of colour-coded polymer shims. Our Polymex® brand is recognised and trusted worldwide as the material of choice for shimming, spacing and insulating.
- Colour-coded thicknesses
- 12–3000µ
- Innovation and development since
- 1980
Our products
Shims, gaskets and shimstock.
PSG Group International pioneered colour-coded polymer shimstock under the trusted Polymex® brand, recognised worldwide for fast, accurate thickness identification and exceptional performance in the most demanding environments.
The Polymex® colour code
No micrometer needed. The colour tells you the thickness.
Non-hygroscopic, oil-resistant, corrosion-resistant and non-conductive. Stocked in the full range at our Hinckley facility, the home of Polymex®.
- Clear 0.012 mm
- Purple 0.025 mm
- Pink 0.037 mm
- Blue 0.050 mm
- Black 0.065 mm
- Green 0.075 mm
- Amber 0.100 mm
- Brown 0.125 mm
- Clear 0.150 mm
- P. Blue 0.175 mm
- Hazy 0.190 mm
- T. Blue 0.200 mm
- Silver 0.225 mm
- White 0.250 mm
- D. Green 0.300 mm
- Natural 0.350 mm
- Red 0.375 mm
- Yellow 0.500 mm
- Hazy 0.500 mm
- L. Grey 0.625 mm
- Blue 0.750 mm
- Tan 1.000 mm
- C. Grey 1.250 mm
- Cream 1.500 mm
- Natural 2.000 mm
- Black 3.000 mm
Colours on screen are indicative. Ask for a physical Polymex® swatch for exact matching.
Shim stack calculator
Which shims make up your gap?
Enter the gap you measured and get the fewest colour-coded Polymex® shims that make it up.
Enter the gap you measured to see the stack of shims that makes it up.
Two premium materials
Our shimstock is manufactured from two premium materials.
Polyester
Polymex® A
Exceptional strength and dimensional stability with outstanding moisture resistance, ideal for precision engineering and high-performance applications.
Polypropylene
Polymex® B
Lightweight, resilient and highly resistant to chemicals, offering excellent versatility across a wide range of industries.

Why choose Polymex® shimstock?
The right shim, at a glance.
Instant identification
Colour-coded thicknesses from 12µ to 3000µ, eliminating the need for a micrometer and reducing assembly errors.
Reliable performance
Non-hygroscopic, oil-resistant, corrosion-resistant and non-conductive.
Flexible supply
Engineered to last
Maintains form under pressure, with excellent insulation properties, low friction and high compressive strength.
Key industries served
Specified where tolerances are not negotiable.
From flight hardware to subsea equipment, Polymex® is the material of choice for shimming, spacing and insulating.
- 01
Aerospace
- 02
Space
- 03
Automotive
- 04
Subsea
- 05
Military
- 06
Industrial
- 07
Bioscience and medical

Materials library
Every gasket and shim material we cut.
Rubber, PTFE, cork, fibre and foam gaskets, Nomex® and Kapton® insulators, thermal pads, engineering plastics and metals, compared in one place: what each one resists, the thicknesses we cut and when to choose something else.
Start with the gasket material chart if you are matching a material to a fluid and a temperature.
Gasket and shim materialsCommon questions
Questions, answered
Can't find what you need? Our technical team is happy to help.
How do I know which material is best for my application?
With the vast range of materials available, selecting the best one is challenging. Our technical team have decades of know-how and will work closely with you to advise on the most appropriate material for your application.
What are the typical lead times?
As every customer's requirements are unique, we always make to order. Provided we have stock available, we can usually work to short lead times, often delivering orders within days.
What are the advantages of Polymex® polymers?
Unique colour-coding provides instant thickness identification. Polymex® products are not susceptible to moisture, so they will not swell or degrade. The material is easily configurable, with excellent insulation properties and high compressive strength.
Have a drawing ready?
Send it to our technical team for a quote on custom shims or gaskets, cut precisely to your tolerances.
Our customers





