Optical fiber cables (180) are installed at an enclosure defining at least one cable port (109) by loading a seal block assembly (120, 140, 220, 340) onto each optical fiber cable (180); installing and/or connecting a fixation assembly (160, 460) onto each optical fiber cable (180); and latching the seal block assembly (120, 140, 220, 340) to the enclosure. The cable (180) is secured by the fixation assembly (160, 460). The fixation assembly (160, 460) retains one or more types of strength members (182, 183) of the optical fiber cable (180). The seal block assembly (120, 140, 220, 340) snaps and/or clips into a locked position relative to the enclosure. A filler rod (502) can be used to fill an unused port in the seal block assembly (120, 140, 220, 340). An attachment device (504) can be used to connect to the filler rod (502) for adding a new tube (510) to the seal block assembly.