Haptic duration scripting

Sorta scripting-noob question (C#): I’m using the below scripts (just the relevant parts) to get haptic feedback, but the best I can do is 3999 microseconds each time, which isn’t very impressive. What do I have to add to allow it to give, say, up to 1 entire second of haptic feedback? (preferably adjustable durations)

 public class NVRHand : MonoBehaviour 
 
 public void TriggerHapticPulse(ushort durationMicroSec = 500, EVRButtonId buttonId = EVRButtonId.k_EButton_SteamVR_Touchpad)
         {
             if (Controller != null)
             {
                 Controller.TriggerHapticPulse(durationMicroSec, buttonId);
             }
         } 

 public class NVRInteractableItem : NVRInteractable 
 
 public NVRHand IsInteracting = null; 
 
 if (IsAttached == true) 
                     {
                         AttachedHand.TriggerHapticPulse (3000);
                     } 

Full disclosure: This is from the NewtonVR control system for the Vive: NewtonVR

Thanks all!