Key specifications - Inner diameter: 39 mm - Intake manifold side outer diameter: 28 mm - Intake manifold side inner diameter: 19 mm What this filter does - Provides filtered air to the engine to support proper air flow and combustion - Helps maintain steady air supply by matching a precise intake geometry - Designed to fit specific air intake system requirements Compatibility and fit - Designed for air intake systems that require the following interface: intake manifold side outer diameter 28 mm and inner diameter 19 mm - The filter bore is 39 mm, which may influence compatibility with your engine’s air intake housing - Verify fit with your vehicle or equipment’s intake components before installation Material and performance notes - Material is not specified in the provided description - Focused on achieving correct dimensions to support proper airflow and engine performance 2-3 use scenarios - Scenario 1: Replacing a worn or degraded filter in an engine whose intake system accepts a 39 mm bore with a manifold interface of 28 mm outer diameter and 19 mm inner diameter - Scenario 2: Upgrading small to mid-size engines or equipment that require precise intake geometry to maintain steady air flow and filtration, such as certain motorcycles, ATVs, or compact generators - Scenario 3: Use in service or retrofit applications where an intake system matches the specified diameters and needs a clean air supply to preserve engine performance