The Kryptonite lock is an Ingersoll Rand

Ingersoll Rand

Ingersoll-Rand plc is a $13 billion global diversified industrial company founded in 1871. The Ingersoll Rand name came into use in 1905 through the combination of Ingersoll-Sergeant Drill Company and Rand Drill Company...

-owned brand

Brand

The American Marketing Association defines a brand as a "Name, term, design, symbol, or any other feature that identifies one seller's good or service as distinct from those of other sellers."...

 of bicycle lock

Bicycle lock

A bicycle lock is a physical security device used on a bicycle to prevent theft. It is generally used to fasten the bicycle to a bicycle stand or other immovable object....

 for securing a bicycle

Bicycle

A bicycle, also known as a bike, pushbike or cycle, is a human-powered, pedal-driven, single-track vehicle, having two wheels attached to a frame, one behind the other. A person who rides a bicycle is called a cyclist, or bicyclist....

 to a pole or other fixture, when the owner wants to leave the bicycle in a public place. The basic design, made of hardened steel of circular cross section bent into a U-shape with a removable crossbar, has been emulated by numerous other manufacturers, and adapted with variations in size and shape for other applications, such as locking motorcycles.

The product was named after kryptonite

Kryptonite

Kryptonite is a fictional material from the Superman mythos —the ore form of a radioactive element from Superman's home planet of Krypton. It is famous for being the ultimate physical weakness of Superman, and the word kryptonite has since become synonymous with an Achilles' heel —the one weakness...

, the fictitious substance that can thwart the powerful comic-book hero Superman

Superman

Superman is a fictional comic book superhero appearing in publications by DC Comics, widely considered to be an American cultural icon. Created by American writer Jerry Siegel and Canadian-born American artist Joe Shuster in 1932 while both were living in Cleveland, Ohio, and sold to Detective...

. The name is used under a limited trademark

Trademark

A trademark, trade mark, or trade-mark is a distinctive sign or indicator used by an individual, business organization, or other legal entity to identify that the products or services to consumers with which the trademark appears originate from a unique source, and to distinguish its products or...

 agreement with DC Comics

DC Comics

DC Comics, Inc. is one of the largest and most successful companies operating in the market for American comic books and related media. It is the publishing unit of DC Entertainment a company of Warner Bros. Entertainment, which itself is owned by Time Warner...

 dating back to 1983.

History

The Kryptonite lock was developed in 1972. Before then, the only comparable security available was from a chain, which could weigh almost as much as the bicycle. (A common humorous observation in bicycle magazines at the time was that the total weight of a bicycle plus chain was constant regardless of cost, since owners of more expensive, lighter bicycles would buy heavier, more secure chains.) In the early 1970s the only proven method to secure one's bicycle was by the use of case hardened security chain with hexagonal links, but some cyclists were making the mistake of using inexpensive chains or cables that could be breached by thieves using commonly available tools. Indeed, local hardware store

Hardware store

Hardware stores, sometimes known as DIY stores, sell household hardware including: fasteners, hand tools, power tools, keys, locks, hinges, chains, plumbing supplies, electrical supplies, cleaning products, housewares, tools, utensils, paint, and lawn and garden products directly to consumers for...

s would often sell inexpensive chain cut to length using simple bolt cutters

Bolt cutters

A bolt cutter, sometimes called bolt cropper, is a tool used for cutting chains, padlocks, bolts and wire mesh. The original use for bolt cutters was as the name suggests to cut bolt seals from shipping containers at the delivery point. It typically has long handles and short blades, with compound...

. The first Kryptonite lock model was made of sheet metal

Sheet metal

Sheet metal is simply metal formed into thin and flat pieces. It is one of the fundamental forms used in metalworking, and can be cut and bent into a variety of different shapes. Countless everyday objects are constructed of the material...

 cut and bent to shape, but the company soon went to the now universal circular cross section.

In an early test of the Kryptonite lock, a bicycle was locked to a signpost in Greenwich Village

Greenwich Village

Greenwich Village, , , , .in New York often simply called "the Village", is a largely residential neighborhood on the west side of Lower Manhattan in New York City. A large majority of the district is home to upper middle class families...

 in New York City

New York City

New York is the most populous city in the United States and the center of the New York Metropolitan Area, one of the most populous metropolitan areas in the world. New York exerts a significant impact upon global commerce, finance, media, art, fashion, research, technology, education, and...

 for thirty days. Thieves stripped the bicycle of every part that could be removed, but the lock resisted all attempts to break it. The innovative U-shaped design of the Kryptonite lock was subsequently adopted by several other manufacturers, with varying degrees of security. U-locks can often be seen holding naked rusty bicycle frames without pedals, gears, or wheels to bicycle racks.

Design

A limitation of the Kryptonite lock is that it is heavy and bulky. Most (apart from the Fahgettaboudit Mini and M18 series) are provided with a plastic carrying bracket that will not fit all frames, nor will it retain the lock when riding over rough surfaces, making transport of this large lock difficult. For that reason many commuter cyclists leave this lock attached to a bicycle rack at their destination, rather than carry it back and forth every trip.

Lock

In 2005, Kryptonite changed their locks from a tubular-key to an I-key, which stopped the ability of a BIC pen

Bic Cristal

The Bic Cristal is an inexpensive disposable ballpoint pen mass-produced and sold by Société Bic of Clichy, Hauts-de-Seine, France.-Background:...

 or other cylinder shaped object from defeating the locking system.

Until 2004, Kryptonite locks used the tubular pin tumbler lock

Tubular pin tumbler lock

A tubular pin tumbler lock, also known as Ace lock; axial pin tumbler lock; or radial lock, is a variety of pin tumbler lock in which 6-8 pins are arranged in a circular pattern, and the corresponding key is tubular or cylindrical in shape....

ing mechanism. Videos circulating on the Internet

Internet

The Internet is a global system of interconnected computer networks that use the standard Internet protocol suite to serve billions of users worldwide...

 demonstrated that some tubular pin tumbler locks of the diameter used on Kryptonite locks could be easily opened with the shaft of an inexpensive Bic

Société Bic

Société Bic is a company based in Clichy, France, founded in 1945, by Baron Marcel Bich known for making disposable products including lighters, magnets, ballpoint pens, shaving razors and watersports products. It competes in most markets against Faber-Castell, Global Gillette, Newell Rubbermaid...

 ballpoint pen of matching diameter.

Vulnerabilities

The three most common methods that can be used to break open Kryptonite locks are the use of a small hydraulic bottle jack

Bottle jack

A bottle jack or whiskey jack is a hydraulic jack which resembles a bottle in shape, having a cylindrical body and a neck, from which the hydraulic ram emerges. They have a capacity of up to 50 tons and may be used to lift a variety of objects. Typical uses include the repair of automobiles and...

 to spring open the lock, an angle grinder

Angle grinder

An angle grinder, also known as a side or disc grinder, is a handheld power tool used for cutting, grinding and polishing.Angle grinders can be powered by an electric motor, petrol engine or compressed air. The motor drives a geared head at a right-angle on which is mounted an abrasive disc or a...

 to cut the U-Lock

Padlock

Padlocks are portable locks used to protect against theft, vandalism, sabotage, unauthorized use, and harm. They are designed to protect against some degree of forced and surreptitious entry.- History :...

 ,or a portable plasma cutting-torch to melt away enough of the U-Lock or chain

Chain

A chain is a sequence of connected links.Chain may also refer to:Chain may refer to:* Necklace - a jewelry which is worn around the neck* Mail , a type of armor made of interlocking chain links...

to allow the frame or securing apparatus to pass through the gap.