251-7222 Air Filter Manufacturer & Supplier for Caterpillar C18 / 3412E Marine Engines

The 251-7222 air filter is a heavy-duty intake air filtration solution designed for Caterpillar marine diesel engines.
We make this air filter in our own manufacturing factory in China, supplying stable quality products for wholesalers, distributors, importers, exporters, and engine service companies.

This model is widely used in Caterpillar C18 and 3412E marine engines, where long operating hours and stable airflow are critical.
As an experienced air filter supplier and OEM manufacturer, we focus on durability, airflow stability, and easy maintenance.

Built-in Air Restriction Indicator

Unlike standard air filters, this 251-7222 model comes with a built-in air restriction indicator, which is commonly requested by marine engine service providers and professional dealers.

• Automatically monitors intake air resistance

• Gives a clear visual warning when the filter is clogged

• Helps operators schedule replacement at the correct time

• Reduces engine downtime and maintenance risk

This feature is especially valued by marine operators, maintenance agencies, and engine service companies.