Slats. "Combat" or 1/4 Slat was automatic, up to around 500 Knts if angles of attack exceeded 5 degrees (signalled by the incidence probe). slightly improved the limits of incidence of the Jaguar that wasn't great as most know. The PTR was originally developed for the Jaguar after the first 2 French "A" prototypes suffered undershoot incidents trying to recover on single engine approaches early in the flight test program. The maximum dry thrust of the Adour 101 was not powerful enough to allow normal approaches at anything above minimum weights, while min burner was too much boost, so PTR was developed "to fill the gap". Of course PTR was almost mandatory for in flight refuelling and some other flight regimes.