Ruyi Jingu Bang

When all of the traditional magic weapons—swords, spears, and halberds weighing thousands of pounds each—fail to meet his standards, the dragon queen suggests to her husband that they give Sun a useless iron pillar taking up space in their treasury.

This is when Sun sees that the weapon is banded with a gold ring on each end, as well as the inscription along the body reading "The Compliant Golden-Hooped Rod.

[4] The inscription indicates that the staff follows the commands of its owner, shrinking or growing to his whim, make copies of itself, and that it is immensely heavy, weighing 17,550 lbs (7,960 kg).

He changes the staff into a titanic red-haired, blue-skinned Yaksha with a club, showing that the predecessor of the Compliant Golden-Hooped Rod has more magical abilities.

Monkey mentions that the Queen Mother of the West had flogged him with an "Iron Cudgel" (鐵棒) on his left and right sides for stealing 10 peaches from her heavenly garden.