Third Substitute (ICS Flag)

An International Code of Signals substitute pennant repeating the third flag or pennant in the same hoist.

Substitutes allow a signal group to contain repeated characters when only one physical set of alphabet flags and numeral pennants is available. Counting starts with the first non-substitute flag at the top of the hoist.

A substitute takes the identity of the flag it repeats; it has no separate message meaning in that position. The full hoist must be assembled and read in the correct order.