Specs located here. It's amazing how compact the SM4 is considering its multitude of features and famed capability. Dimensions are 130mm x 124mm x 48mm (Length x Width x Height). Both the SM4 and stock ECU can comfortably fit on a magazine as shown in the picture below. Weight of the SM4 is only 0.5 kg.
Contact Toby Lee @ GT Auto if you're interested in the Autronic SM4. An ECU no matter how capable is only as good as the person doing the installing/mapping/tuning and this is where Toby makes the difference! For example, how many people will send my stock throttle body's IACV (Idle Air Control Valve) to Autronic Down Under for a better idle map to improve idle quality? Price is not cheap though in the low five figure range for a new unit. This ain't no E-Manage though..