To support real-time 3D kinematic applications, Movella introduces the MTw Awinda, a highly accurate miniature wireless inertial motion tracker. This new product eliminates the requirement for inter-tracker cabling, uniquely enhancing the freedom of movement and flexibility of use of traditional inertial based movement analysis systems. At the same time, the fundamental advantages of inertial technology compared to e.g. optical-based systems are preserved, namely: cost effectiveness, highly accurate drift-free orientation, and robustness to occlusion. This paper describes the basic working principles and architectural choices of the MTw Awinda system.