The Envir-o from Charles Austen Pumps provides aeration in packaged sewage treatment plants. The simple, efficient pumping principle uses an electromagnetically operated diaphragm, eliminating sliding parts and keeping wear and tear minimal. It incorporates energy-efficient motors for low power consumption. The design has a compact alloy casing that is weatherproof and does not degrade over time. It is available in steps from 30 l/min to 200 l/min. The range is CE and UL approved. A built-in alarm system detects low pressure in the airline, alerting users via a loud buzzer and LED warning light. 770/831-1122; www.bluediamondpumps.com.