RJ45 dust covers install in any standard RJ45/LAN slot keeping the open ports on switches/routers/blanking panels/network cards & media converters safe from dust & debris - RJ45 port blockers prevents network errors & potential downtime caused by dust and debris in open slots - Snap-in RJ45 protective covers are easy to insert & remove without disrupting adjacent ports or cables - 100 pack RJ45 female jack caps are easy to order & store - 2 year warranty on these Ethernet port protectors.