ICS meaning: Code / Answer, Understands the Hoist or Numeric Decimal Point.
“The flag that follows is from the International Code of Signals.”
Code answer pennant is used by a receiving vessel to indicate that it understands the hoist. Also, it’s used at the end of a signal to indicate it’s complete. The pennant is hoisted by the receiving vessel as each hoist of the transmitting ship is seen.
Easy to hoist and replace
Can withstand harsh weather
Modern technologies and materials → best value for money