"Iron hooks can be fastened to residual leg limbs, providing a kind of graceless, scraping locomotion for their wearer."
Hooks For Feet is a physical defect that occupies the foot slot in exchange for 4 mutation points. They provide no AV or DV, but count as a weapon with 4 penetration and 1 damage. They also reduce your movement speed by 10.
If you manage to get your feet dismembered and regrow them while having this defect, you will regrow normal feet and be able to wear shoes like any normal character. However, the movement speed penalty is permanent and cannot be removed.