Hole plug

A hole plug for plugging a hole of a plate material, comprising;

• a head portion;
• a leg portion protruding from the head portion;
• and
• a flange portion protruding on an upper circumference of the leg portion, wherein the hole provided in the plate material is blocked by the hole plug in a state where the leg portion is inserted, for locking, to the hole of the plate material until the flange portion abuts against the plate material and is controlled,
• wherein the leg portion includes an inner wall having an approximately cylindrical shape and connected to the head portion;
• and an outer wall extending along the inner wall with a gap with respect to the inner wall from a folded portion provided in an end portion of the inner wall, and forming a bendable thin-walled portion in one portion thereof, and
• the thin-walled portion is capable of transitioning from a first usage condition in which the outer wall is locked in the hole with the thin-walled portion being in a non-bending state, to a second usage condition in which the outer wall contacts the hole with a force larger than the first usage condition, by the outer wall being bent elastically at the thin-walled portion by an outer force.