Compact 2phase linear stepper assembly (Model A) for low‑voltage DC control. Available for DC 5V or DC 12V systems, this 2phase 4wire stepping unit converts rotary motion to precise linear travel using a screwandnut slider. Size and stroke options are offered to fit compact automation and motion tasks: 15mm or 20mm diameter options, with stroke choices listed as 35mm or D 22mm. Why choose this unit Precise, repeatable linear movement: the screw nut slider delivers controlled axial travel for positioning tasks. Lowvoltage compatibility: designed for DC 5V or DC 12V systems for easy integration with common controllers and power supplies. Standard stepper interface: 2phase 4wire wiring matches widely available stepper drivers and controllers, simplifying installation. Compact form factor: available in 15mm or 20mm diameters to suit spaceconstrained applications. Key attributes Voltage: DC 5V or DC 12V (select according to your system). Phasing/wiring: 2phase, 4wire configuration. Size options: 15mm or 20mm diameter options. Stroke options: 35mm stroke and D 22mm stroke (choose the stroke length required for your application). Function: Linear screw nut slider converts stepper rotation into linear travel. Model reference: Stepping electronic starter A. What this solves Replaces bulky linear actuators with a compact, integrated screwandnut slider for accurate shorttravel motion. Provides a straightforward plugin solution when you need controlled linear displacement from standard stepper control signals. Avoids custom machining by providing a readymade linear motion element sized for small assemblies. Typical applications Small automated camera or sensor slides where compact, repeatable linear movement is required. Laboratory or desktop automation (valve actuation, micropositioning, sample handling) needing lowvoltage step control. Light robotics and hobbyist CNC/automation projects that require a precise short stroke linear actuator compatible with common stepper drivers. Installation and compatibility tips Confirm voltage (5V or 12V), diameter (15mm or 20mm), and stroke (35mm or D 22mm) before ordering to ensure mechanical and electrical fit. Use a compatible 2phase stepper driver or controller for reliable motion control. Mounting and coupling should match the chosen diameter and stroke; verify clearance and travel limits in your assembly. Available options let you select the combination of voltage, diameter, and stroke for your project while retaining a standard 2phase 4wire interface and the screwnut slider function for dependable linear motion.