Amazon.com: uxcell 35 Pack, M4 Cage Nut, Carbon Steel Nickel Plated for Server Shelf Cabinet : Electronics
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Au-Ve-Co Products - 1/4-20 Screw, 0.064 to 0.105" Thick, Spring Steel Cage Nut - 67741488 - MSC Industrial Supply
Amazon.com: kwmobile Cage Nut Insertion/Removal Tool - Cage Nut Tool for Installation and Extraction of Cage Nuts in 10 Inch and 19 Inch Network Cabinet Racks : Automotive