STANDARD RECIRCULATION Disk Drive The Standard Recirculation Filter (SRF) is comprised of an electrostatic filtration media encapsulated between two layers of protective scrim. The SRF is designed to provide protection from particles. The high efficiency, low pressure drop construction provides optimized particle clean-up performance. The SRF is located directly in the path of the airflow generated by the rotating disks. In a hard disk drive, this location is typically opposite the read/write arm. The installation of the filter into the drive can be accomplished by several techniques. The most common method is to insert the filter into a holder integral to the base casting. Alternative methods include inserting the filter into a slot in a plastic bracket or ultrasonically welding the filter to the plastic bracket. The plastic bracket, in turn, is custom designed to fit into the base casting.

STANDARD RECIRCULATION FILTER (SRF) PRODUCT GUIDELINES AND SPECIFICATIONS Contamination Control In-house cleanliness testing performed routinely. Designed to pass the most stringent cleanliness specifications. Manufactured in a cleanroom environment 3.5" HDD PARTICLE CLEAN-UPTIME (0.1 MICRON PARTICLES) Time (seconds) Contact Donaldson today for more information! Seoul, Korea Hong Kong Disk Drive Standard Recirculation Filter (07/10) © 2010 Donaldson Company. All Rights Reserved. Information in this document is subject to change without notice.