Plastic base gasket for quarter window assembly. Porsche 911

Plastic base gasket for quarter window assembly.
A precision-moulded plastic base gasket that sits between the quarter-window hinge/base and the body. It reproduces the OE profile to seal the mounting footprint, protect paint, and set the correct standoff so the glass and latch align properly.
Sold each, 2 required.

Fits:
Porsche 911/912 1965 - 1977

Diagram ref no 18

• Application: Rear quarter window assembly (pop-out/hinged type) – Porsche 911
• Side-agnostic; sold each (order two if renewing both sides)

Function:
• Seals the hinge/base to the body to prevent water and dust ingress
• Protects paintwork from abrasion and crush marks
• Helps maintain correct window alignment, closing pressure, and reduced wind noise

Over time, the original quarter window base gaskets can harden, flatten, or shrink due to age, UV exposure, and temperature changes. This can cause water leaks, wind noise, or rattles, and may even lead to paint scuffing around the hinge area.

Replace the gasket when:
 • Performing glass or hinge installation, or during body/paint restoration
 • The window shows misalignment, wind noise, or minor leakage
 • The existing seal appears cracked, brittle, or misshapen

 Replacing with a fresh gasket restores a tight seal, clean alignment, and factory-quality protection for your classic Porsche 911.

Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.

90154349121

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