When sourcing a 12v linear actuator, you must prioritize the Load Capacity (Push/Pull force), which typically ranges from 100N to over 6000N. Ensure the Speed (mm/s) aligns with your application; generally, higher loads result in slower speeds. The 50mm Stroke Length is fixed, but you must verify the Retracted Length (Installation Dimension) to ensure it fits your spatial constraints. Additionally, check the Duty Cycle (e.g., 10% or 2 minutes of continuous use followed by 18 minutes of rest) to prevent motor burnout.