Mercedes W221 Door Window Sealing Rail Rear Left N/S A2217350965

Visual condition of the part

The product shows signs of use visible in the photos.

Mercedes W221 Door Window Sealing Rail Rear Left N/S is an original body component from the Window seals and rails group, designed for installation in the rear left door. It ensures a tight fit of the window to the door frame, reducing noise, vibrations, and water ingress into the vehicle interior.

Specifications and technical data

• SKU: A2217350965
• Mark: Mercedes (Genuine OE)
• Condition: Used
• OEM Part Number: A2217350965
• Substitutable numbers: A2217350965, A 221 735 09 65
• Location on the vehicle: Rear, Left
• Part type: Outer Beltline Seal
• Category: Window Seals, Gaskets & Trims

Purpose and function of the component

The rear left window sealing rail in the Mercedes W221 class is responsible for stable window guidance and maintaining proper sealing between the glass and the door panel. A correctly selected component of this type:

• limits the ingress of water and moisture into the door interior,
• reduces wind noise at higher speeds,
• supports the proper operation of the window lifting mechanism,
• protects the edge of the glass from excessive wear.

Thanks to its dedicated fit for the specific body model, the seal works with the factory door frame, maintaining the correct geometry and sealing line.

Compatibility and fit for Mercedes W221

The offered rail has been designed specifically for the rear left window in the Mercedes W221 class, which means its profile, length, and shape are adapted to the factory door construction. Placement on the vehicle: rear – left side eliminates the risk of errors when selecting the part and facilitates service work planning.

The original origin from the Mercedes brand translates into maintaining factory fitment standards, as well as compatibility with other window and door trim components.

Performance characteristics and installation

As a component from the Window seals and rails category, the product is designed to work in variable weather conditions, with frequent window opening and closing cycles. The construction of the seal allows for:

• maintaining flexibility within the typical operating temperature range,
• stable seating in the door slot,
• cooperation with the factory window lifting mechanism.

The component comes from disassembly, which in practice means it is a used part, but one that retains the functionality required for further operation. For workshops and private users, this represents a cost-effective solution while maintaining the manufacturer's original specifications.

Practical application and benefits of replacement

Replacing a worn or damaged window seal in the rear left door allows for restoring acoustic comfort and reducing the risk of corrosion inside the door. The main benefits include:

• more stable window operation without jamming or play,
• reduced window fogging due to better sealing,
• protection of the interior upholstery against moisture,
• maintaining the aesthetics of the side body line.

For premium vehicles such as the Mercedes W221, using an original sealing rail allows for maintaining the structural and visual consistency of the entire door zone.

Part selection and additional information

Before purchasing, it is worth verifying the compatibility of the component with your specific vehicle, especially regarding the body version and the installation side. The product has an assigned OEM part number and interchangeable numbers, which facilitates unambiguous identification in service catalogs and parts selection systems.

If you are planning a comprehensive repair or upgrade of the window and door zone in your Mercedes and need other components from the same group, such as additional rails, guide seals, or window trim elements, check the available parts in the Mercedes window seals and rails category.

When deciding to use a used part, it is worth considering different service strategies – the guide material Refurbished or used original – which part to choose for repair? may be helpful, as it discusses the practical aspects of choosing components from disassembly compared to refurbishment.