R.J. Enterprises - RJ45 Jack Dust Cover, Cap, Protector, Blue (Price per bag of 100p) DC-0-BL Dust cover for RJ-45 Jacks, Patch Panels, Data Centers, Home Networks, etc. Protect against moisture & dust build up in unused ports. Prevents the erosion of ethernet contact points. Solidly Built & Reusable. Softer elastic plastic for snug fit. Tabbed for easy insertion/removal. Space efficient. Will not interfere with adjacent ports. Designed for high density application. Available in 8 colors for color coding. 100 pieces per bag. U.S. Patented. UL Approved