SG Turbo Blowers from Howden Roots are designed to provide plant operators with efficiency across the actual operating range. Exceptional turndown capability is built in as standard to ensure that when plants are operating at low load, the efficiency of the aeration system is unaffected. They are available in a choice of 15 frame sizes with a capacity flow of up to 80,000 cfm. With achievable efficiency levels exceeding 87 percent, the blowers maintain effectiveness through the full flow range, including the key 60 to 80 percent window and dropping to as low as 40 percent capacity when required. 800-557-6687; www.howdenroots.com