In a previous article (Laranjeira et al.), a network model was developed to describe and predict the behavior and performance of NETmix (R), a new type of static mixer consisting of a network of interconnected chambers and channels. This work reports experimental results on a transparent prototype NETmix (R) unit constructed to enable the characterization of the mixing mechanisms at the local scale. Tracer flow visualization experiments show that the mixing characteristics in the NETmix (R) unit depend on the Reynolds number both for macromixing and micromixing. A critical Reynolds number for the onset of mixing was obtained where oscillating flow in the chambers is observed. Chemical reaction experiments were done using test reactions systems that exhibit mixing effects in the final product distribution and selectivity. Reaction selectivity was shown to depend on the reactants injection scheme. Theoretical predictions obtained with the network model were in agreement with experimental data for high Reynolds numbers. (C) 2010 American Institute of Chemical Engineers AIChE J, 57: 1020-1032, 2011