Coolant Reservoir Cap for VW Golf Polo Passat T5 T6 Touran Caddy Skoda Octavia Fabia Audi A1 A3 A4 A5 A6, Replacement Coolant Reservoir Cap Cover 3B0121321

OE Reference - Manufacturer References Compliant: Replacement part conforms to original part numbers 3B0121321 and 95810644700. Maintains the dimensions and technical specifications of the original model for installation without modification; matches the original part.
Structural Material - Composition and Mechanical Properties: Made of injection-molded ABS plastic. Resistant to abrasion, corrosion, and dust; withstands engine compartment temperature variations (-40°C to 120°C) without structural deformation, ensuring a stable service life.
Sealing and Pressure Function - Role in the Cooling System: Ensures a hermetic seal for the coolant reservoir and regulates internal pressure (0.9-1.1 bar). Prevents coolant leakage and limits the ingress of dirt and moisture into the system, protecting the cooling system.
Direct Installation - Tool-Free and Modification-Free Installation: Direct replacement for the old cap. No additional tools or adjustments required, positioning on the original tank location
Vehicle Compatibility - Full list of supported ranges: Compatible with VW Golf (2003–2022), Polo (2001–...), Passat (2000–2014), T5 (2003–...), T6 (2008–...), Touran (2003–2015), Caddy (2004–...), Jetta (2005–2010); Audi A1 (2010–2018), A3 (2004–2021), A4 (2002–2016), A5 (2007–2017) and A6 (2010–2018); Seat Ibiza (1993–2018), Leon (1999–2021), Toledo (1998–2019) and Cordoba (1993–2009); Skoda Fabia (1999–2021) and Octavia (1996–2021)