These are used for fastening and mounting 3.5" Hard Drive hot swap Caddy TRAY. #6-32 x 1/8" Countersunk head Screws. Newest SAS and SATA 3.5" HDD bottom hole screws reduce the depth penetration. 6-32UNC x 1/8" Screws is designed specially for 3.5" HDD Bottom Mounting Holes, and also suitable for Side mounting holes.
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