A lock has a shell, an internal sleeve and a locking rod assembly. The shell has multiple protrusions formed inside the shell. The internal sleeve is mounted rotatably in the shell. The locking rod assembly is mounted in the internal sleeve and has multiple locking rods. Each locking rod has a cut selectively aligning with the protrusions in the shell. When the cuts of the locking rods align with the protrusions in the shell, the internal sleeve can be rotated relative to the shell to change the lock or unlock status of the lock.
