A stent graft deployment device assembly (10) has a cylindrical fixed handle (6) to be gripped and held by a user and an tubular release handle (30) extending through the fixed handle. The release handle can be moved through the fixed handle. The deployment device assembly has a pusher assembly and a sheath (18) to cover a stent graft on the pusher assembly. The pusher assembly is connected to the fixed handle and the sheath is connected to the release handle so that retraction of the release handle through the fixed handle causes the sheath to be retracted from the stent graft on the pusher assembly. The fixed handle has a rotator component (36) with internal first and second screw threads. The tubular release handle has an external screw thread (31) which engages with the first screw thread. The external screw thread (31) can extend along part, all or in segments along the release handle. A release clamp (48) on the pusher has pins which engage with the second screw thread. Movement of the rotator component with respect to the fixed handle first moves the tubular release handle with respect to the fixed handle and subsequently moves the release clamp on the pusher and thereby pulls the trigger wires.