Abstract: A connector having two connector portions which are adjustably connected together to be in aligned relationship and with each portion receiving the respective ends of optical fibre lines to be connected together in abutting and aligned relationship. At least one connector portion has an inner collar in which the end of the fibre is disposed to lie in eccentric relationship to the longitudinal axis of the collar. This inner collar is rotatably disposed in a hole in an outer collar with the hole being eccentrically disposed with respect to the longitudinal axis of its outer collar. By angular adjustment of the inner and outer collars with respect to each other the respective ends of the optical fibre lines can be positioned with respect to each. At least one inner collar can be of transparent material so that optical leakage occurring at the connector can be easily detected.