• Three-Dimensional Design:
  
  Its triangular prism shape provides a stable, "stereo" grip that is
  
  easier to pick up from flat surfaces compared to standard flat rulers.
• Rainbow Refraction:
  
  Due to its prism-like structure, the ruler can refract sunlight to
  
  create a rainbow effect, a popular aesthetic feature for "Ins style"
  
  stationery.
• Dual-Sided Markings:
  
  Clear metric scales (0–15cm) are often marked on multiple edges,
  
  allowing for precise measurements and straight-line drawing without
  
  smudging.
• Material & Durability:
  
  Most models are crafted from high-quality, shatterproof acrylic or
  
  plastic, making them lightweight (approx. 20g) yet durable enough for
  
  daily school or office us