According to The Guinness book of Records in 1983, this was the largest working padlock in the world. It measures 20" x 14" x 3", weighs 28lbs and is made of stainless steel.

Click image for larger version.  Name: 2408-02-500.jpg  Views: 39  Size: 230.4 KB  ID: 15906 Click image for larger version.  Name: 2408-03-500.jpg  Views: 27  Size: 122.7 KB  ID: 15907 Click image for larger version.  Name: 2408-04-max.jpg  Views: 26  Size: 632.2 KB  ID: 15908

I just wondered if this record has now been broken, or indeed what other large working padlocks are known around the world.

PS: This one is now part of the HoL collection.