Flight 144’s Ariane 4 has been fitted with the four solid propellant
strap-on boosters that will provide additional thrust during liftoff and
ascent when the vehicle is launched on September 25.

The Flight 144 launch vehicle is a 44P variant of the Ariane 4 family,
equipped with the four strap-ons. This mission will mark the 15th – and
final – launch of an Ariane 44P as the Ariane 4 family nears the completion
of its operational career.