Genuine 21396-P20-000 Automatic Transmission Case Vent OEM

The Genuine 21396-P20-000 is an OEM automatic transmission (AT) case vent designed to factory specifications for Honda and Acura vehicles. This small but essential component allows internal transmission pressure to equalize with the atmosphere, preventing pressure buildup that could force transmission fluid past seals and gaskets.

As a genuine OEM part, it is manufactured to the exact tolerances and material specifications required for a proper, leak-free fit — ensuring reliable performance and a direct, no-modification installation.

Key Features:

• OEM Genuine Honda Part — manufactured to factory specifications
• Transmission Case Vent — relieves internal pressure to protect transmission seals
• Part Number: 21396-P20-000
• Direct OEM replacement — no modifications required
• Ensures proper transmission venting and fluid retention

This genuine transmission case vent is the correct factory replacement for vehicles originally equipped with this component, delivering the same fit, form, and function as the original part.