Cable Matters (5-Pack) LC Duplex Multimode Fiber Keystone Jack in Ivory LC FIBER KEYSTONE INSERT is compatible with Multimode OM1, OM2, OM3, OM4 and 50 micron or 62.5 micron fiber patch cords; Fits a standard opening in a patch panel, wall plate or surface mount box for keystone jacks LC FIBER COUPLER joins two duplex multimode fiber patch cables with low profile LC connectors; Protective dust caps on the adapter prevent dirt from contaminating the fiber keystone jack or multimode fiber cables DUPLEX LC ADAPTER with a flangeless design, phosphor bronze sleeve, and stainless steel retention clip accommodates zipcord fiber cables; Fiber keystone will not block the zipcord yoke when changing polarity of the cord STURDY SNAP-IN CONSTRUCTION of LC fiber feed-thru coupler keystone provides a secure connection; Removable dust caps prevent contamination when not in use; Installation of female to female keystone insert provides a professional looking installation in the home or office COST-EFFECTIVE 5-PACK provides spare keystone jack inserts for last minute cable connections; Re-usable keystone jack inserts with dust caps can be easily disconnected and relocated when upgrading