Lots of riders use the mini Kryptonite New York as it's one of the most secure locks around, not for fashion reasons.

Other lock puzzles stem from the necessity to invent secure locks in the Middle Ages.

The second version features touch-screen capability instead of a movable laptop and more secure digital locks.

Older hotels have been repainted, fitted with secure locks, up-to-date fire alarms and even, in some cases, in-room microwave ovens.

"Wasn't a very secure lock anyway."

Hardly the most secure lock built, but it did make me feel, for the briefest of moments, like James Caan in Thief.

It was not a very secure lock at best, and, under the skilful fingers of the midnight visitor, it quickly gave way.

But before he left, this cute single man surveyed my apartment and told me I should have more secure locks on my sliding-glass doors.

"The most responsible thing you can do it keep them under secure lock and key."

Make sure they twist to a secure lock at any position on the tube.