A modular connector is provided having a connector plug, which may be inserted into an associated socket in a first longitudinal direction, a resilient leg, depending at a first end thereof from the connector plug, and having a depressible part, distal therefrom, depressible towards the connector plug, and a guard cover, configured to prevent access to the depressible part of the resilient leg in its direction of depression, but to permit access to the resilient leg in the longitudinal direction through an access aperture, the access aperture being aligned with the depressible part of the resilient leg on an axis parallel with the longitudinal direction, to allow depression of the resilient leg through the access aperture directly. Corresponding extraction tool and methods, loopback connector, blanking plug, keyed protrusions and notches, security gasket, and blanking plate and patch panel also are disclosed.