Create your ideal windows below, or contact the team if you have a specific requirement.

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Note: Unless stated, all windows are sized to fit into rubber seals. If you need bolt-in sizing, then please contact us.

Regular price $295.00 USD
Regular price Sale price $295.00 USD
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Orders ship in 3 weeks (5 for hard-coated). Delivery in 3–17 business days, depending on location.

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Product information

Race Plastics polycarbonate windows are handcrafted to order by our expert UK team. Designed for motorsport and high-performance use, they’re lightweight, tough, and completely shatterproof—unlike glass or standard acrylics, which can crack under stress.

Our standard windows use 4mm polycarbonate to meet Motorsport UK regulations. We also offer 5mm options that are FIA compliant, plus hard-coated variants for added durability and resistance to scratching.

All windows are available in clear, bronze, or grey tint to suit your vehicle’s design. You can also add window sliders to either or both front doors, depending on your setup.

Window Sliders

Each slider kit is made from the same polycarbonate as your chosen windows. Designed for both driver and passenger sides, these sliders are reliable, practical, and easy to install.

Choose between:

  • Three-position locking with a smooth, rattle-free action
  • Simple two-position setup for fast and secure use

Sliders are engineered to avoid scratching and sit flush with your window kit. Ideal for improving airflow on track days or road builds. More info is available on our Window Slider Kits page.

Shipping times

Once your order’s confirmed, we’ll get started. Most standard orders are manufactured and dispatched within 3 weeks. Custom or hard-coated versions may take a little longer—we’ll contact you with a lead time. If you need your order by a specific date, let us know and we’ll aim to meet it.

Can I fit the windows myself?

Yes, installation is usually straightforward. There are helpful videos online, and our windows are designed to fit into standard rubber seals unless otherwise noted. If you need bolt-in variants, just contact us.

Can I collect my order?

Collection from our UK facility is available by arrangement. Most international orders are shipped, but we’re happy to sort collection if needed—just get in touch.

Want to change your order?

Reach out as early as possible. We’ll always try to accommodate changes, but if manufacturing has already started, there may be a charge.

  • Expertly crafted in the UK

    All of our windows and sliders are hand made to order by our team in the UK.

  • Motorsport compliant

    Our standard windows are made from UK compliant 4mm Polycarbonate.

  • FIA & hard-coated options

    We also offer FIA compliant 5mm & hard-coated options.

  • Road legal warning

    Always check your local vehicle regulations before fitting.

Not found what you need?

Need a single window, or have a special requirement, no problem. Just let us know what you need.

The BMW E21 3 Series Coupe rally car

The BMW E21 3 Series Coupe isn’t just another classic, this was the car that kick-started one of the most iconic performance lineages in automotive history. Born in 1975 as the first-generation 3 Series, the E21 was designed to blend everyday usability with a proper driver’s experience. But let’s be honest, what made it truly shine was its motorsport potential.
While the E21 wasn’t officially built for rally or touring car racing straight from the factory, that didn’t stop enthusiasts from turning it into a proper competition machine. With its rear-wheel-drive setup, lightweight chassis, and a selection of punchy inline-four and inline-six engines, it became a go-to choice for privateer racers and tuners looking to push the limits. BMW itself got in on the action with the 320 Group 5, a fire-breathing, wide-body turbocharged monster that tore through the European Touring Car Championship in the late ‘70s. It was loud, it was aggressive, and it made sure everyone knew BMW was serious about racing.
None of that front-wheel-drive nonsense here. The E21 gave drivers the pure, connected feel that made BMW famous. The 323i, with its 2.3L inline-six, had the kind of sound and pull that made you want to keep shifting just to hear it sing. It wasn’t the fastest thing in a straight line, but it handled like a dream and begged to be thrown into corners. More importantly, it was a modder’s paradise. Strip it down, tweak the suspension, slap on some fat fenders, and you had a serious competitor on the rally stage or the track. And then there was the Group 5 320 Turbo, an absolute animal with 600+ horsepower, a gigantic wing, and a presence that screamed ‘get out of my way.’
Although its successors, like the E30 M3, often steal the spotlight, the E21 laid the foundation for BMW’s motorsport dominance. It was a workhorse in touring car championships and a hidden gem in the rally world, where its nimble handling and strong power-to-weight ratio made it a fun underdog against AWD competitors. Today, it remains a favourite among historic racing enthusiasts who want to relive the golden days of analogue driving.
If you ever see an E21 tearing through a rally stage or carving up a circuit, you know you’re looking at a piece of BMW history, an old-school coupe that still knows how to have a good time.

Thought about a slider kit?

Our easy retro fit window slider kits are the essential addition to your racing windows with standard and advanced kits available.

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Need Glue for your New Windows?

  • Why Polycarbonate Windows?

    Learn about what polycarbonate windows are, what benefits they offer and why you should use them.

    Find out why 
  • Perspex or Polycarbonate Windows?

    Find out which you should use for your race windows, why, and which one will protect you the most whilst racing.

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  • Our Frequently Asked Questions

    Get the answers to key questions on products and services, including deliveries, collections and timescales.

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