4-Way Cross Connector

An aquarium cross air line fitting, often referred to as a 4-way cross connector or cross-shape airline connector, is a specialized plastic or metal component used to split a single air source into three or four separate outputs, or to connect multiple air lines in a complex network. These fittings are essential for distributing airflow from one air pump to multiple decorations, airstones, or sponge filters within one or more tanks.