President Duterte issued Proclamation No. 1169, declaring a 10-day period of national mourning from June 24 to July 3 over the passing of former President Benigno S. Aquino III, during which the National Flag shall be flown at half-staff/half-mast.
However, not all Flags can be flown at half-mast: Sometimes the Flag is flown directly attached to a flagpole without a halyard. Sometimes the flag is displayed indoors in a flagstaff and accompanying stand. Sometimes the Flag, attached to a fixed flagstaff, is used in a parade of colors. Sometimes the flag is not flown at all but hung vertically against the wall.
In such cases, NHCP recommends that in lieu of flying the National Flag at half-mast, black ribbon/s may instead be tied at the finial (in case of fixed flagstaffs) or at the two corners of the hoist (for Flags hung vertically) as a sign of mourning.