The APC ACPA4000RF NetworkAIR PA4000 Replacement Filter collects and removes condensation from the air conditioner. It removes dirt and other particulates from the intake air for cleaner supply air. Allows the user to determine when the unit operates, saving energy costs. This self-contained solution does not require an external condenser, refrigerant piping or building water source for operation. Heat is rejected to a drop ceiling or adjacent area via a flexible duct kit. The NetworkAIR PA can be installed quickly and inexpensively, without the need for building modifications.