expression.Duration
expression Required. An expression that returns one of the objects in the Applies To list.
Example
The following example adds a shape and an animation to that shape, then sets its animation duration.
Sub AddShapeSetTiming()
Dim effDiamond As Effect
Dim shpRectangle As Shape
'Adds shape and sets animation effect
Set shpRectangle = ActivePresentation.Slides(1).Shapes _
.AddShape(Type:=msoShapeRectangle, Left:=100, _
Top:=100, Width:=50, Height:=50)
Set effDiamond = ActivePresentation.Slides(1).TimeLine.MainSequence _
.AddEffect(Shape:=sh, effectId:=msoAnimEffectPathDiamond)
'Sets duration of effect
effDiamond.Timing.Duration = 5
End Sub