\section{Conclusion}
\label{conclusion}

This paper presented two human subject studies aimed at better understanding the role of visuo-haptic rendering of the hand during virtual object manipulation in OST-AR.
The first experiment compared six visual hand renderings in two representative manipulation tasks in \AR, \ie push-and-slide and grasp-and-place of a virtual object.
Results show that a visual hand rendering improved the performance, perceived effectiveness, and user confidence.
A skeleton rendering, providing a detailed view of the tracked joints and phalanges while not hiding the real hand, was the most performant and effective.