The Whirlwind Linear Air Pump from Septic Services can be used for new septic installations or for upgrading existing 40, 60, 80 or 100 Model air pumps. It is available in five models: the STA40 produces 1.7 cfm airflow and is recommended for tanks up to 500 gpd. The STA60N produces 2.6 cfm for tanks up to 500 gpd. The STA80N produces 3 cfm for tanks up to 750 gpd. They come with an integrated hose bib for a low-pressure alarm. The STA80AL model has an integrated audible alarm to monitor pump performance. The STA100 model produces 6 cfm for tanks up to 1,000 gpd. Designed for easy maintenance, the pumps don’t require lubrication and provide easy access to the filter compartment for inspection and replacement without the need for tools. 800/536-5564; www.whirlwindairpumps.com.