Features The PCB copper coating process is upgraded to 2oz (copper thickness is 70um, normal is 35um). With high copper content, the heat dissipation performance is of course better. Good quality, soldered and gold‑plated pin headers, strong and durable, has a long service life. SMT placement machine manufacture, higher yield rate and more stable performance. Small size, easy to carry and store, convenient to use and with 5pcs module, can meet your use demand. Specification: Item Type: Stepper Motor Driver ModuleWeight: Approx. 3.7 g / 0.1 oz (with heat sink) Special Note: Red board Rs is 0.1Ω, current upper limit is 2A Package List:5 x Stepper Motor Driver Module 5 x Aluminum Block Package List 5 x Stepper Motor Driver Module 5 x Aluminum Block