Abstract: Couplings for hoses and the like having externally threaded male components and internally threaded female components provided with tube inserts projecting from one component into slide fit engagement with the other component for aligning the threaded portions of the components as they are brought together for threaded engagement. To further facilitate alignment of the components, the internally threaded female component has an unthreaded smooth extension for sliding over the externally threaded male component to align the thread. The tubular extension member may be a separate auxiliary tube bottomed in the female coupling unit and held in position by a resilient washer, such as is conventionally used between the coupling units. Alternately the tubular extension may be a fixed part of one of the coupling components. The extension tube and the extended smooth leading end of the internally threaded female member can be used together or separately.