The screw securing the knob or handle on vodozabornoy valve (valve, tap), made of bronze or brass. If it’s lost or fallen into disrepair — not to screw in its place steel, even briefly, thereby creating future additional problems. It will rust very soon, and remove it from the stock will be difficult, if not impossible. Take a screw of copper (in extreme cases, of aluminum) rivets. If rivets not, it is possible to “plant” of a suitable piece of appropriate wire.
GLUKHOV, Saransk