St. Louis, MO., Jan. 30, 2006 – Aerospace Filtration Systems Inc. (AFS) and Donaldson Company Inc. (NYSE:DCI) have teamed to develop industry-leading solutions for new and retrofit inlet barrier filtration systems for helicopters. The AFS/DCI team will pursue development of both commercially certified and military qualified filter assemblies that use a new Donaldson proprietary dry filter media and a durable new oiled media.

New-development filters for the Bell 407X, AS 350, Agusta A119 and several military helicopters are being considered from the initial design phase to incorporate the dry media. The dry media simplifies service with the use of compressed air or an environmentally friendly cleaning solution and water, eliminating the time and attention required to dry and re-oil filters. The team will evaluate existing applications for retrofit as time allows within the regulatory approval process, making the dry media solution available to customers in the future. The majority of AFS systems will be offered with oiled media as a baseline and an option for the dry media, depending on customer preference and design requirements.

“Use of a new dry media, only available from the industry experts at Donaldson, will provide operators a more simplified and environmentally friendly servicing option,” said Michael Scimone, president of AFS. “The new dry media will be integrated on development systems and is planned for retrofit to existing systems based on the needs of the application. For those applications where oiled media is the most viable solution, an oiled media will be employed.”

“We are pleased to partner with AFS on the production and delivery of this advanced barrier filter technology,” said Sheila Peyraud, general manager of Aerospace and Defense at Donaldson Company. “We design our filters to meet the challenges of the most demanding operating environments and this collaboration will benefit both companies and our customers as we work together to provide the best filtration systems available.”

AFS and Donaldson barrier filtration systems have been proven to filter out more than 99 percent of dirt and sand. Barrier filter systems actually enhance engine performance when compared to traditional particle separators, deliver more engine temperature margin (thus more load carrying capacity), and provide a greater margin of safety. Other benefits include reduced operating and overhaul costs and reduced engine operating temperatures for increased engine life.

About Aerospace Filtrations Systems, Inc.

AFS is the rotorcraft industry leader in the design, development and manufacture of high-performance engine IBF systems for commercial and military rotorcraft propulsion systems. AFS has delivered more than 1,300 systems and 12,000 filters to military and commercial customers worldwide for main engine inlets and Auxiliary Power Unit (APU) inlets. In addition to the Bell 407X system, the company also produces certified commercial filtration systems for the Bell 206B, Bell 407, the Bell 206L-3/4, Bell 206L-1/C30 and the MD 369 (MD 500H/D/E/F Series). AFS military systems are available for the Bell OH-58D Kiowa Warrior, Bell UH-1H Huey, Bell OH-58A/C, Boeing AH/MH-6J/M Little Bird, Sikorsky UH-60 Blackhawk main engine and APU, Boeing AH-64 Apache APU, and Boeing CH-47 Chinook APU.

About Donaldson Company, Inc.
Donaldson is a leading worldwide provider of filtration systems and replacement parts. Donaldson is a technology-driven company committed to satisfying customer needs for filtration solutions through innovative research and development. Donaldson serves customers in the diesel engine and industrial markets including in-plant air cleaning, compressed air and gas purification, power generation, disk drive filtration, aerospace and defense, off-road equipment and trucks. Our 11,000 employees contribute to the company’s success at over 30 manufacturing locations around the world. Donaldson is a member of the S&P MidCap 400 Index and Donaldson shares are traded on the NYSE under the symbol DCI. Additional company information is available at www.donaldson.com.

AFS will display its IBF systems at booth 1289 at Heli-Expo, Feb. 26-28 in Dallas, Texas.


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For more information, contact:

Aerospace Filtration Systems, Inc.
Jay Foster
Sales and Marketing Manager
(636) 300-5050
foster@afsfilters.com

Donaldson Company, Inc.
Jay Wilson
Account Manager
(952) 887-3968
jdwilson@mail.donaldson.com