Master Lock

Master Lock is an American lock manufacturer that produces low security padlocks, chain locks, gun locks, and various other lock related equipment. Master Lock is currently the world's largest importer of padlocks and related security products. They are best known for their laminated steel layer padlocks that use warded and pin-tumbler designs. Their combination padlocks are also widely used on lockers in schools throughout the United States.

History
Master Lock was founded in 1921 by Harry Soref, P.E. Yolles, and Sam Stahl. Soref invented and patented a padlock in 1924 that used laminated layers of steel for extra protection. Padlocks of the time were all hollow and suspectible to various forced entry techniques, particularly impact with a hammer. Soref's inspiration for the design was from bank vault doors and battleships of the time.

Soref's design went on to be wildly successful, with federal agents placing large orders. Many of these padlocks were used to lock down establishments that disobeyed prohibition laws.

In 1939 Master Lock moved to their current facility at 2600 North 32nd Street, Milwaukee, Wisconsin. Harry Soref died in 1957. He was succeeded as president of Master Lock by co-founder and long time friend Sam Stahl.

American Brands acquired Master Lock in 1970. American Brands was renamed to Fortune Brands in 1997. In 2014, Master Lock acquired SentrySafe. Fortune Brands Innovations owns Master Lock along with American Lock and SentrySafe.

"Tough Under Fire" campaign
In 1973, Master Lock ran a famous Super Bowl ad where one of their locks survived being shot by a sharpshooter, thereby proving its durability, thus the slogan "Tough Under Fire". Master Lock would continue running similar ads during future Super Bowls, spending almost their entire annual marketing budget on the single commercial.

In the episode "Mega Movie Myths" of the Discovery Channel's show MythBusters, this famous ad was tested by shooting a Master Lock padlock by a rifle. Master Lock padlocks passed the test when shot with a 9mm and .357 handguns, but were defeated by shotguns and Garand rifles. The official Mythbusters verdict was not "busted," but rather "plausible." They argued that using such strong firearms at close range may cause ricochet and spalling which would be extremely dangerous to a real-life attacker.

Keyed padlocks

 * Master Lock No 1
 * Master Lock No 2
 * Master Lock No 3
 * Master Lock No 4
 * Master Lock No 5
 * Master Lock No 6
 * Master Lock No 7
 * Master Lock No 8
 * Master Lock No 15
 * Master Lock No 17
 * Master Lock No 19
 * Master Lock No 21
 * Master Lock No 22
 * Master Lock No 25
 * Master Lock No 27
 * Master Lock No 29
 * Master Lock No 40
 * Master Lock No 82
 * Master Lock No 121
 * Master Lock No 130
 * Master Lock No 140
 * Master Lock No 141 / 142
 * Master Lock No 150
 * Master Lock No 160
 * Master Lock No 170
 * Master Lock No 185
 * Master Lock No 187
 * Master Lock No 190
 * Master Lock No 192
 * Master Lock No 192
 * Master Lock No 193
 * Master Lock No 194
 * Master Lock No 195
 * Master Lock No 196
 * Master Lock No 197
 * Master Lock No 198
 * Master Lock No 205
 * Master Lock No 220
 * Master Lock No 230
 * Master Lock No 311
 * Master Lock No 315
 * Master Lock No 380
 * Master Lock No 392
 * Master Lock No 410
 * Master Lock No 450
 * Master Lock No 475
 * Master Lock No 510
 * Master Lock No 517
 * Master Lock No 532
 * Master Lock No 570
 * Master Lock No 575
 * Master Lock No 576
 * Master Lock No 605
 * Master Lock No 911
 * Master Lock No 930
 * Master Lock No 2240
 * Master Lock No 6271

Combination padlocks

 * Master Lock No 175
 * Master Lock No 975
 * Master Lock Speed Dial
 * Master Lock Sphero