     self.transform = CGAffineTransform(scaleX: 0.0, y: 0.0)
 	self.willShowHandler?()
     UIView.animate(withDuration: self.animationIn, delay: 0,
-      usingSpringWithDamping: 0.7,
-      initialSpringVelocity: 3,
+      usingSpringWithDamping: self.springDamping,
+      initialSpringVelocity: self.initialSpringVelocity,
       options: UIViewAnimationOptions(),
       animations: {
         self.transform = CGAffineTransform.identity

          self.dismissOnBlackOverlayTap = value
        case let .showBlackOverlay(value):
            self.showBlackOverlay = value
        }
      }
    }

  open var showBlackOverlay: Bool = true
  open var highlightFromView: Bool = false
  open var highlightCornerRadius: CGFloat = 0
  open var springDamping: CGFloat = 0.7
  open var initialSpringVelocity: CGFloat = 3


  // custom closure
  open var willShowHandler: (() -> ())?
