Buyers must prioritize the Safe Working Load (SWL) or Rated Capacity, ensuring it exceeds the maximum intended lift by a safety margin. Key technical factors include the number of sheaves (which determines the mechanical advantage), the sheave diameter-to-rope diameter ratio (D/d ratio) to prevent wire rope fatigue, and the material grade (typically 35CrMo or 45# forged steel). Additionally, ensure the hook features a 360-degree swivel design with high-quality thrust bearings for smooth rotation under load.