A directional lock or a headgear or interface assembly has one or more directional locks that include a catch arrangement for initiating or assisting in movement of a lock member of the direction lock. In some configurations, the catch arrangement assists movement of the lock member in only a portion of a range of travel of the lock member. In some configurations, the directional lock has a housing and a sleeve and the catch arrangement has a catch arm carried by the sleeve. The catch arm includes a catch end that contacts the lock member, which can be a lock washer in some configurations.